Knowability

Synthese v.173, No. 1, 2010

2010-02-15T11:12:00.002+11:00

My special issue of Synthese, Knowability and Beyond, is now available in its entirety online. Highlights include three papers, indeed the only papers i know of, that embrace and modify Edgington's 1985 rigidifying stategy for dealing with the knowability paradox. This makes me happy since i was unable to acquire an adequate representation of her influential work in my Oxford volume. Also therein you'll find a continuation of the debate between Tennant and Williamson on whether there is a knowability paradox for Cartesian restricted knowability principles, and Michael Fara's long awaited paper on the distinction between knowability and the capacity to know. And there are other great papers by Kvanvig, Hand, Routley (reprint), and Proietti and Sandu.

EUROPEAN JOURNAL FOR PHIL SCIENCE

2009-11-02T10:08:00.001+11:00

News from Franz Huber:

The European Philosophy of Science Association (EPSA) is pleased to
announce the launch of its new journal:

EUROPEAN JOURNAL FOR PHILOSOPHY OF SCIENCE (EJPS)

Editor-in-Chief: Carl Hoefer (Autonomous University of Barcelona, Spain)
Deputy Editor: Mauro Dorato (University of Rome III, Italy)
Associate Editors: Franz Huber (Konstanz, Germany), Edouard Machery
(Pittsburgh, USA), Michela Massimi (London, UK), Samir Okasha (Bristol,
UK) and Jesús Zamora (UNED, Spain).
The Editorial Team will be assisted in its work by an Editorial Board of
highly reputed philosophers of science from around the world.

EJPS is the official journal of EPSA and will appear three times a year,
beginning in January 2011. EJPS intends to publish first-rate research in
all areas of philosophy of science, and now welcomes submissions via the
on-line portal.

The Journal’s website (still partly under construction) is here.

European Philosophy of Science Association (EPSA): http://www.epsa.ac.at

The 2010 Synthese Conference

2009-10-27T04:38:00.000+11:00

I just received this from Vincent Hendricks

On April 15th and 16th of 2010, the Synthese Conference will take place at Columbia University. The 2010 edition of the Synthese Conference will focus on the theme of epistemology and economics. Recent years have seen an increasing amount of interaction between epistemology and economics: traditional topics in epistemology, such as the analysis of knowledge, have found a significant role in the study of interactive decision making, while traditional topics in economics, such as the analysis of rationality, now figure prominently into certain areas of epistemology. We anticipate that the conference program will include slots for five invited papers and at least five contributed papers. Every paper that is presented at the conference will be considered for the special issue of Synthese that will be based on the conference theme of epistemology and economics. The list of invited speakers is still being finalized. In the meantime, we encourage submissions for the contributed slots. Submissions should be relevant to the conference theme of epistemology and economics, broadly construed, and should satisfy the usual guidelines for submissions to Synthese. Submissions for the contributed slots must be received no later than February 1, 2010. Notifications of acceptance will be made by February 20, 2010. All submissions should be sent to synthese.conference.2010@gmail.com .

Editorial Updates

2009-10-19T06:04:00.003+11:00

Thanks to those of you still staying tuned to Knowability. Hope to get back to posting some philosophy in the near future. For now two pieces of news that i'm happy to report.

My special issue of Synthese, Knowability and Beyond, is slowing becoming available online as the authors get their proofs back to the publisher. Here's my introduction. Also currently available from the issue is Michael Hand's paper, "Anti-realism and Universal Knowability", which utilizes the typically overlooked difference between pragmatic and non-pragmatic reasons for the unperformability of a proof.

Also, New Essays on the Knowability Paradox, became available in August. That project was a labor of love, taking 6 years to get to print. It includes Alonzo Church's two referee reports on Fitch's 1945 paper regarding Fitch's counterfactual definition of value, and includes the first two formulations of the knowability paradox. The volume includes a reprint of Fitch's 1963 paper, where the result was first published, and 19 new essays covering various aspects of the discussion.

Crispin's New Research Program

2009-10-18T03:00:00.002+11:00

The Northern Institute of Philosophy now exists. This is the new research program directed by Crispin Wright. The structure and mission of the program is outlined on the website, and will include the launching of a new journal, provisionally titled The Northern Light, that will specialize in short sharply focused papers.

PhilPapers

2009-01-28T11:54:00.002+11:00

An incredible resource for published and unpublished online philosophy papers was just made public by Dave Chalmers at the Centre for Consciousness. Having had the opportunity to test drive PhilPapers before the launch, I can say without hesitation that it is by far the best resource we have in our field for tracking the most recent and not so recent papers in any area of philosophy. More info on Dave's blog.

SEP Entry Revised

2008-09-22T14:53:00.002+10:00

My Stanford Encyclopedia entry on the Church-Fitch paradox of knowability (coauthored with Berit) was recently updated and is now online.

Epistemology: 5 Questions

2008-09-08T13:37:00.004+10:00

Vincent Hendricks and Duncan Pritchard just published a really fun book of interviews with leading epistemologists. It's called Epistemology: 5 Questions. Here are the 5 questions:

Why were you initially drawn to epistemology (and what keeps you interested)?
What do you see as being your main contributions to epistemology?
What do you think is the proper role of epistemology in relation to other areas of philosophy and other academic disciplines?
What do you consider to be the most neglected topics and/or contributions in contemporary epistemology?
What do you think the future of epistemology will (or should) hold?

Mmm. Sweet and Sour Humans Again

2008-08-18T20:35:00.006+10:00

Just posted this on my human rights and atrocities montage. Found it relevant and a good excuse to exhibit the beautiful yet disturbing Grace Jones, who hasn't shared any recordings since 1989.

Choice and Necessary Implicaton: or How to Beat a Torture Rap

2008-06-20T14:04:00.004+10:00

Yesterday Trenton Merricks gave a great talk on Truth and Freedom. He argued that a class of fatalist arguments of the form below are question begging and that their first premise is false.

1. It was true a thousand years ago that Jones sits at time t (where t is a few moments from now), and Jones has no choice about that fact.

2. Necessarily, if it was true a thousand years ago that Jones sits at t, then Jones sits at t.

Therefore,

3. Jones has no choice about his sitting at t.

He demonstrated his point by replacing all occurrences of 'was true a thousand years ago' with 'will be true a thousand years from now'.

My own reaction is that both arguments are invalid. They fallaciously rest on the principle that failing to have a choice (regarding the truth of a proposition) is closed under necessary implication. Let NC be the factive operator 'has no choice that', so that 'sNC(p)' says 'it is true that p, but person s has no choice about it'. Then the above argument has the following form:

1*. sNC(p)

2*. Necessarily, p implies q.

Therefore,

3*. sNC(q)

We see that this is an instance of the closure principle. But counterexamples to the principle are not hard to find. Let p be the true proposition that person A at time t has tortured some detainees at Gitmo. B clearly has no choice about p (because B doesn't know about A's activities). But our proposition (that p) necessarily implies that somebody at some time tortured some detainees at Gitmo. It would follow by the above argument that B had no choice about whether somebody at some time was tortured at Gitmo. However, B himself tortured some detainees there, and so did in fact have a choice about whether some detainees were tortured.

A defense of the Merricks analysis over the one favored here might include the following objection. Even though B had a choice about torturing detainees he did in fact torture, he didn't have a choice about whether some detainees were tortured. After all, he had no choice about what others would do without his knowledge, and those others happened to torture some people. The problem with this objection is that it entails that neither A nor B had a choice about whether some detainees were tortured (even though, we may suppose, A and B were the only ones willfully torturing). More generally, nobody ever has a choice about any existential proposition that more than one person makes true! In sum, if we supposed NO-Choice is closed under necessary implication, we've already conceded too much to the fatalist.

Glitter and Doom

2008-05-07T11:56:00.002+10:00

As many of you may know, Tom Waits doesn't tour much. But when he does it is super entertaining. He's passing through a number of cities soon, including St Louis at the Fox Theater on June 26.

Madison Epistemology

2008-04-11T15:06:00.002+10:00

Couple great epistemology conferences approaching in Madison:

Wisconsin Epistemology Workshop is taking place on the UW-Madison campus May 3-4, featuring Earl Conee, Richard Feldman, Ernie Sosa, Alvin Goldman, Timothy Williamson, and (as commentator) Jim Pryor. This conference is organized by Juan Comesana, and is sponsored by The Anonymous Fund and the Berent Enc fund of the UW-Madison Philosophy Department.

The Fifth Annual Formal Epistemology Workshop takes place on the UW-Madison campus May 15-18. The workshop is sponsored by the Philosophy Departments at UW-Madison, Berkeley, UT-Austin, and Carnegie Mellon.

[HT: Sandy Goldberg]

Knowability and Beyond

2008-04-07T20:08:00.002+10:00

My issue of Synthese is now finalized. I've included below the contents and a link to my introduction. I expect it to go into production in the near future.

SYNTHESE: Knowability and Beyond

Editor's Introduction
"Williamson's Woes" Neil Tennant (OSU)
"Antirealism and Universal Knowability" Michael Hand (Texas A&M)
"Possible Knowledge of Unknown Truth" Dorothy Edgington (Oxford)
"Knowability and the Capacity to Know" Michael Fara (Princeton)
"Fitch's Paradox and Ceteris Paribus Modalities" Carlo Proietti (Paris) and Gabriel Sandu (Paris)
"The Incarnation and the Knowability Paradox" Jonathan Kvanvig (Baylor)
"Necessary Limits to Knowledge: Unknowable Truths" Richard Routley Sylvan (ANU) [REPRINT]

Must and Can

2008-02-20T20:52:00.005+11:00

In “Modals and Conditionals Again” Angelica Kratzer treats natural language ‘must’ as the expression of a two-place relation between a premise set and a proposition. The trick is getting the relation straight. Consider the following 'must' claims:

Deontic: “One must not microwave kittens!”

Doxastic: “In light of what Jack mistakenly believes, Jill must be in love with him.

Epistemic: “Oh…, the gun must have been loaded.”

Dispositional: “If you must smoke, then please use an ashtray (and not my rhododendra)”

Bouletic: “You must wear that fabulous dress”

For Kratzer the two-place relation is 'must in view of', giving

Deontic: “In view of our duties, one must not incinerate kittens”

Doxastic: In view of what Jack mistakenly believes, Jill must be in love with him.

Epistemic: “In view of what we now know, the gun must have been loaded.”

Dispositional: “If, in view of what you are disposed to do, you must smoke, then use an ashtray”

Bouletic: “In view of what my preferences state, you must wear that fab dress”

The natural way to read these claims is as follows:

'In view of premise set A it must be that p' is true iff
p follows from A.
And the corresponding dual operator 'can' is read:

In view of A it can/might/may be that p iff
p is compatible with A.
Two well-known problems emerge for this sort of semantics. First it forces a vacuous reading of 'must' claims that relate a proposition to an inconsistent premise set. And second, it gives rise to all sorts of unwelcome modal collapses, and relatedly, forces a vacuous reading of 'must' claims that relate non-contingent propositions to premise sets. In my talk at Kioloa, I criticized a proposal by Kratzer for dealing with the first problem. I then argued that the two problems are related and sketched a unified solution.

Kratzer's proposal tells us that ‘musts’ and ‘cans’ follow from the appropriate consistent subsets of the given premise set. More specifically, let A be an inconsistent premise set of, say, legal judgments.
A = {p, ~p, q}And let X be the set of all A’s consistent subsets.
X = {ø, {p}, {~p}, {q}, {p, q}, {~p, q}}Kratzer’s proposal says:

"In view of A, it must be that p" is true iff
each set in X has a superset in X from which p follows.
The problem with inconsistent premise sets, of course, is that they entail everything. However, it is false that each set in X has a superset in X from which an arbitrary proposition follows. So, unlike the natural proposal with which we began, Kratzer's proposal doesn't predict the absurd claim that, in view of the law, we must commit murder.

However, the restriction not only blocks the application of 'must' to arbitrary propositions, but it blocks the application of 'must' to any contradicted premise. So claims like the following are predicted to be false:

"In view of what Graham believes, the Liar sentence must be true"
"In view of what Graham believes, the Liar sentence must not be true".

Moreover, Kratzer's proposal always blocks the application of 'must' to premises responsible for the inconsistency and it sometimes blocks the application of 'must' to important consequences that (at least partially) depend on at least one of the contradicted premises.

Here's an example of the latter type of case. White House chief of staff “Scooter” Libby was convicted of obstruction of justice and making false claims to federal investigators during the CIA leak investigation. Bush commuted his prison sentence from 33 months to 0 on the grounds that any term of imprisonment for such nonviolent first offenses by experienced government service employees is too harsh. This contradicts US federal sentencing guidelines and practice, which prescribe hard time for such offenders. In view of federal sentencing guidelines, what now must be prescribed for the sentencing of a like criminal c for like crimes? It would be irresponsible to let Bush’s incompetence and nepotism overly influence the federal justice system. Hence, in view of federal sentencing guidelines, c must do hard time.

But Kratzer’s view doesn’t predict this. For it depends on at least one contradicted legal judgment---viz., criminals of this sort are to do hard time. And when that is the case, it will be false that, for each consistent subset of the sentencing guidelines, there will be a superset among them from which it follows that c is to do hard time.

A second problem with the Kratzer proposal is that it says nothing about what to do when the proposition p fails to be a contingent matter. When p is necessarily true, then it follows from every set. Therefore, in every context, p must be the case. For instance, the view predicts that, in view of what Michael (the intuitionist) believes, excluded middle is correct. But Michael the intuitionist denies the unrestricted truth of excluded middle. To pick another example of this kind, we want to say that Obama might actually win in November. But suppose in fact Hillary wins. Then in view of what we know it must be that Hillary actually wins. That's because 'Hillary actually wins' is necessarily true (if true). So, in view of what we know, it must be that actually Hillary will win. But then, by the duality of the operators, it is false that in view of what we know Obama might actually win.

The problem of inconsistent premise sets and the problem of collapsed modals are at root the same problem. In each case we assume that the deontic/doxastic/epistemic/legal/bouletic "possibilities" are a subset of the logical possibilities. And that is not how it should be. After all, in view of what we know, it may be that Goldbach’s conjecture is false. Ex hypothesi, it’s true. And, for all we knew before the telescope, Hesperus might not have been Phosphorus. And, for all we know right now, Obama might actually be the next US president. Ex hypothesi, Clinton wins.

The view I proposed in Kioloa was this:

'In view of A, it must be that p' is true
iff
all the relevantly similar (possible or impossible) A-worlds are p-worlds.

'In view of A, it can be that p' is true
iff
some relevantly similar (possible or impossible)
A-worlds are p-worlds.
I treat 'musts' as counterfactuals because the corresponding strict conditional, which would quantify over all possible and impossible worlds, would be too strong and rarely (if ever) come out true. The corresponding 'can' claims would be too weak and would usually (if not always) come out true. The important insight is that, with the introduction of impossible worlds, we drop the assumption that the relevant accessibility relation is a subset of S4/S5 accessibility. In so doing, we block the familiar modal collapses and the special problems of inconsistent premise sets, and we get that much closer to the correct understanding of 'must and 'can'.

Epistemology Beach Update

2008-02-19T10:58:00.008+11:00

Epistemology at the Beach

Below is an update on what the workshop participants were going on about. Pics are here, and here.

Patrick Greenough argued that Stanley's certainty account of assertion doesn't work. Among the counterexamples were warranted assertions of future contingents, for which the relevant brand of certainty is virtually impossible to achieve.

I responded to some of Angelica Kratzer's recent work on 'must' and 'can'. Kratzer thinks about 'must' claims as 'must in view of claims'. (Will post on some of this soon.) The view I defended was this: 'In view of premise set A, it must be that p' is true iff 'p' is true at all the relevantly similar (possible or impossible) A-worlds. This gives us the right predictions for cases of inconsistent premise sets and awkward cases where p is not a contingent matter (e.g., "in view of what Dummett believes it must be that excluded middle is false").

Yuri Cath argued against the view that knowledge-how is a species of knowledge-that. The strategy was to construct cases of knowledge-how (e.g., knowledge how to juggle) for which the relevant corresponding beliefs (e.g., that w is a way to juggle) are Gettiered or corresponding justification for such beliefs is defeated.

Brent Madison discussed the question of whether causation is necessary for epistemic basing. He argued that contrary to what is presupposed in much of the literature on basing relations, Lehrer's case of the gypsy lawyer doesn't undermine the requirement.

Stephen Hetherington disagreed with the orthodox belief that all Gettier cases are cases of knowledge failure. The discussion was driven by a pretheoretic intuition about the kind of luck that generates Gettier's original cases.

Declan Smithies defended a JJ-principle---viz., one is justified in believing p only if one is justified in believing that one is justified in believing that p. He argued that it explains various Moorean paradoxes and the role of justification in critical reflection.

Dave Chalmers sought an epistemic constraint on truth that avoids the Church-Fitch paradox of knowability. Dave takes it that each basic truth is knowable by somebody. Let 'b' express the conjunction of all the basic truths. All non-basic truths are knowable in the sense that someone is in a position to know that p is materially implied by b.

Daniel Star defended his view that a fact X is a reason for an agent N to F just when X is evidence that N ought to F.

Berit discussed the knowledge argument (construed as an argument against a priori physicalism). She defended it against a number of objections, including the old fact reply and the missing concepts reply.

Wolfgang Schwartz took issue with the standard interpretation of Frank Arntzenius' example of the traveler who in fact passed the mountains on her way to Shangri-La. It is usually treated as a case where the traveler must eventually update to .5 her credence that she came by way of the mountains, lest she violate the principle of Indifference. Wo, by contrast, defended the view that she should retain the credence she had when passing the mountains (viz. 1), lest she violate Conditionalization and Reflection.

Jonathan Schaffer closed the workshop with a paper about a brand of skepticism which threatens the broadest range of knowledge. Knowledge entails basing. Hence, any knowledge (even a priori knowledge and the cogito) is threatened by the debasing demon who, at the final stage of the basing process, intervenes to make it the case that the otherwise properly based belief is based on a guess or wishful thinking. The demon covers his tracks by leaving the victim with no indication that the normal process has been tampered with.

Epistemology at the Beach

2008-02-15T01:56:00.003+11:00

Epistemology at the Beach is a workshop this weekend hosted by Dave Chalmers' Centre for Consciousness and Daniel Stoljar's Basic Knowledge grant and organized by Declan Smithies. The location is the ANU Coastal Campus. I'll try to blog the event.

Participants: Jonathan Schaffer, Patrick Greenough, Berit Brogaard, Joe Salerno, Brent Madison, Yuri Cath, Wolfgang Schwartz, Declan Smithies, Daniel Star, David Chalmers, Stephen Hetherington, Daniel Stoljar, Susanna Schellenberg, David Bourget, Aisling Crean, JC Bjerring, John Cusbert, Holly Lawford-Smith, Masafumi Matsumoto, Doug Edwards, Federico Luzzi, Paul Dimmock, Grant Reaber, Fiona MacPherson and Stuart X.

Talks
Friday
Patrick Greenough: Assertion, Knowledge and Certainty
Joe Salerno: Must and Can

Saturday
Yuri Cath: Knowing How Without Knowing That
Brent Madison: Causation and the Epistemic Basing Relation
Stephen Hetherington: Gettiered Knowledge
Declan Smithies: Critical Reflection and Epistemic Responsibility
David Chalmers: Knowability and Scrutability

Sunday
Daniel Star: Reasons: Explanations or Evidence?
Berit Brogaard: On the Knowledge Argument
Wolfgang Schwartz: I’m Certain That I Went By The Mountains
Jonathan Schaffer: The Debasing Demon

John Hawthorne: Wade Memorial Lecturer

2008-02-05T20:01:00.000+11:00

For more info contact John Greco
jgreco2 AT slu DOT edu

Intuitionist Truth and the Paradox of Idealization

2008-01-21T13:39:00.000+11:00

What I did in my commentary at the Eastern APA is frame a debate about Fitch's paradox, and explain the significance of Salvatore Florio and Julien Murzi’s contribution to the intuitionistic reply. Along the way I tried to improve on their main argument.

Consider the following epistemic theories of truth, which are supposed to differ
precisely on the strength of the advertised relation between truth and knowledge.

Semantic Idealism (SI): p(p Kp)

Necessarily, all truths are in fact known (by some finite being at some time).

Strict Finitism (SF): p(p FKp)

Necessarily, all truths are feasibly knowable = necessarily, all truths are are knowable by beings who have precisely the cognitive capacities that we at some time happen to have.

Moderate Anti-realism/Weak Verificationism (WVER): p(p Kp)

Necessarily, all truths are knowable by us in principle (i.e., by beings whose capacities are at best finitely better than those we happen to have).

And consider the following brand of realism, which denies all three positions.

Realism (R): p(p & ~Kp)
There may be unknowable truths---i.e., truths that couldn’t be known given any finite extension of our cognitive capacities.

The three brands of anti-realism appear to be listed in the order of their logical strength, from strongest to weakest. (SI) entails (SF) entails (WVER), and the entailments are not meant to go the other way. Indeed, (WVER) gains its plausibility to the extent that it can distance itself from awkward forms of idealism and strict finitism.

The Church-Fitch paradox is a proof that threatens to show that moderate antirealism collapses into idealism. A classical formulation of Florio and Murzi’s paradox of idealization (presented at the APA) threatens to show that (WVER) collapses into (SF). The lesson of either is that so-called "moderate anti-realism" is an inherently unstable position. In the context of that epistemic theory of truth, the apparently modest idealization is equivalent to at least one of the immodest idealizations. Simply put, a so-called moderate anti-realist can’t distinguish between actual knowledge, feasible knowability, and knowability in principle.

I put the lessons this way for simplicity of exposition, although stating them as I
have presupposes excluded middle. The Florio-Murzi proof aims to draw related lessons without excluded middle, and thereby aims to show that an independent commitment to intuitionistic logic can't rescue the moderate anti-realist from the grips of Fitch-like paradoxes.

The key concept in the Florio-Murzi discussion is the concept of an ideal agent. They define it as any finite agent whose epistemic capacities are better than our own. Their proof requires that it be a priori that there are no ideal agents. Since humans may be cosmic hicks, as it were, F and M must not mean "human capacities" by "our capacities". After all, it is an a posteriori matter whether there are beings in the universe with epistemic capacities better than those of humans. So I take it that by 'ideal agent' they mean any finite agent whose capacities are better than any actual finite agent. This provides the desired strength to the first premise of the Florio-Murzi proof:

1. There are no ideal agents.

The second and most critical assumption in the Florio-Murzi proof is that
there is a truth q that isn’t feasibly knowable. Indeed, their assumption requires that it be necessary that anyone who knows q is an ideal agent. Call this assumption epistemic modesty. It is presumed that even the moderate intuitionistic anti-realist is epistemically modest in this sense.

2. (Epistemic Modesty) There is a feasibly unknowable truth; that is, a truth such that necessarily any being that knows it is ideal:
q(q & x(Kxq Ix))

Epistemic modesty is meant to be a more precise denial of Strict Finitism. F and M foreshadow the following kind of objection to (Epistemic Modesty). Can't we have a cognitive twin in a world with a more favorable set of epistemic resources or environment? In such a world subjects with our cognitive capacities are in a position to know q, even though we in the actual world are not. Beings internally like us, but in improved external circumstances, acquire knowledge more easily than we do. For instance, suppose that cognitive limitations prevent any actual being from determining the location of a particular distant star. Nevertheless, there will be possible worlds where our telescopes are better or the cosmic environment for whatever reason better preserves the brightness of stars over longer distances. In such worlds, beings with precisely our cognitive capacities come to know a truth that is feasibly unknowable in the actual world.

Such considerations threaten the plausibility of (Epistemic Modesty). I don’t believe that Florio and Murzi said enough in their paper to dispel the worry. But here is a quick fix. Redefine an ideal agent more generally as one who has a finitely improved epistemic state of information, where states of information include the subject’s cognitive capacities, resources and environment. And let q be a truth that can’t be known by beings in any actual epistemic state of information. Then (Epistemic Modesty) is more intuitive. When q is a truth that we're not in a position to know (owing to our cognitive, material and environmental limitations), then by definition knowing q necessitates being in a better epistemic state. That is, necessarily, if x knows q then x is an ideal agent in that she is epistemically better off---i.e., she has either increased cognitive capacities, better epistemic resources, or a more epistemically friendly environment.

With these adjustments the Florio-Murzi proof is much stronger. It has the following structure. Assumptions I through III entail a contradiction:

I. (No Ideal Agents) There are no ideal agents.
~xIx

II. (Epistemic Modesty): There is a feasibly unknowable truth.
q(q & x(Kxq Ix))

III. (WVER): All truths are knowable in principle.
p(p Kp)

An illuminating version of the proof goes like this:

Rests On	Premise	Justifiction
0	0. p(p Kp)	[WVER]
1	1. ~xIx	[No Ideal Agents]
2	2. q	[A for CP]
3	3. x(Kxq Ix)	[A for Reductio]
3	4. x(Kxq Ix)	[from 3]
3	5. Kaq Ia	[from 4]
6	6. Ka(q & ~xIx)	[A for reductio]
6	7. Kaq & Ka~xIx	[6 by K-distributivity]
6	8. Kaq	[from 7]
3,6	9. Ia	[from 5 and 8]
3,6	10. xIx	[from 9]
6	11. q & ~xIx	[6 by K-factivity]
6	12. ~xIx	[from 11]
3,6	13. Contradiction	[from 10 and 12]
3	14. ~Ka(q & ~xIx)	[6-13 by reductio]
3	15. ~Ka(q & ~xIx)	[from 3, 4-14, since only necessities follow from necessities]
3	16. ~Ka(q & ~xIx)	[15 by def. of ]
0	17. (q & ~xIx) Ka(q & ~xIx)	[from 0]
0,3	18. ~(q & ~xIx)	[from 16, 17]
1,2	19. q & ~xIx	[from 1, 2]
0,1,2,3	20. Contradiction	[18, 19]
0,1,2	21. ~x(Kxq Ix)	[3-20 by Reductio]
0,1	22. q ~x(Kxq Ix)	[2-21 by CP]
0,1	23. q(q ~x(Kxq Ix))	[22 by -Intro]
24	24. q(q & x(Kxq Ix))	[Epistemic Modesty]
0,1,24	25. Contradiction	[from 23 and 24]

As F and M point out, the proof is intuitionistically valid. However, I don’t think it gains any ground, over and above Fitch's paradox, against the intuitionistic strategy. The intuitionist is happy to deny the epistemic modesty principle---i.e., that there are feasibly unknowable truths:

i. ~q(q & x(Kxq Ix))

After all, existence for the intuitionist is constructive existence, and we can’t construct an example of a feasibly unknowable truth.

The typical charge against this sort of maneuver is epistemic hubris. But the typical reply is for the intuitionist to regain her modesty by replacing the original modest assumption with a claim that is classically but not intuitionistically equivalent. For instance, she might deny that every truth is feasibly knowable:

ii. ~q(q x(Kxq & ~Ix))

Classically i. and ii. contradict. But not intuitionistically. There are more intuitionistic distinctions than there are classical distinctions, and the intuitionist usually takes advantage of this fact. Contrary to what I thought at the APA, the move won't work in this case, since ii contradicts line 23 of the proof. Line 23 rests only upon WVER and No Ideal Agents.

The intuitionist at this point might chose some other more complicated classically (but not intuitionistically) equivalent formula with which to express her modesty. Surely there is at least one that doesn't intuitionistically contradict line 23. The move should be followed with an explanation of why this, rather than the original formula, best expresses her epistemic modesty.

There is, however, a recommendation to preempt this intuitionistic maneuver. It is based on a suggestion raised by F and M in their paper. First and foremost, don’t assume the existence of a feasibly unknowable truth. Instead begin with a proposition that would be feasibility knowable, regardless of its truth value. For instance, let q be the sentence ”There is life on x”, where x is some planet that is epistemically inaccessible in the relevant sense. Our cognitive capacities, or overall epistemic state of information, is inadequate for the determination of whether or not q. So we should be modest about q and about ~q. The commitment is to a proposition q such that: necessarily if an agent knows q then she is ideal, and necessarily if an agent knows ~q then she is ideal.

iii. x(Kxq Ix)
iv. x(Kx~q Ix)

Notice that we don’t presuppose the constructive existence of a feasibly unknowable truth. But we still get a contradiction. Line 23, which rests just on WVER and NO IDEAL AGENTS, shows us that the assumption q together with iii jointly entail a contradiction. Hence, ~q. And by analogous reasoning ~q and iv jointly entail a contradiction.

If the intuitionist already has some other way of expressing her modesty she can give up at least one of iii and iv. She is still not committed to Strict Finitism, but she will be committed to some principle classically, but not intuitionistically, equivalent to Strict Finitism. There is logical space for her to do so. But she will have to tell some complicated story to regain an epistemically modest footing.

Contrary to what I thought at the APA, I don't believe that the Florio-Murzi paradox of idealization raises new difficulties for moderate intuitionistic anti-realism---that is, difficulties over and above those already raised by the Church-Fitch paradox. However, I think it highlights the significance of knowability paradoxes more generally. Such paradoxes show us that if we treat truth as an epistemic notion, then we blur modal epistemic distinctions that are needed to make such theories plausible.

Both Kinds of Philosophy: Country and Western

2008-01-14T04:17:00.000+11:00

More updates from the Arizona Ontology conference. Our pictures are on our Facebook. Carrie Jenkins has great pics on her page.

John MacFarlane, seen here, defends a paper co-written with Niko Kolodny, in which they argue that there isn't a subjective 'ought' for deliberation and a separate objective 'ought' for advice. Rather, there is just one assessment-sensitive 'ought' that can explain it's dual role in deliberation and advice.

Daniel Nolan argued that, of nomological necessity, there are no quantities in between the fixed quantities that quantum physics deals with. There is a physically important sense in which the hydrogen atom, jumping from -13.6eV to -3.4eV, couldn't have passed through states -10eV or -5.1eV. The fundamtental quantities of quantum reality are discrete.

The thesis of Ted Sider's paper was that neither existence monism nor priority monism has legs. For instance, priority monism, the thesis that no natural features are had by any object other than the world-object, entails that every sub-world object has all the same natural features, both intrinsic and extrinsic. To make a long story short, priority monism can't explain the rich structure of the universe.

Jenann Ismael gave an exciting paper arguing that the notion of objective chance appears in physics much earlier than most philosophers suppose. It is implicit even in classical mechanics! Indeed, it was argued, that one can't do physics without ruling out various possibilities in a way that is guided by objective chance.

Berit and I discussed essence, limit assumptions about relevance, and our impossible worlds approach to counterfactuals. Overall, the conference was philosophically very rich and a great deal of fun.

Ontology Western Style

2008-01-11T11:44:00.000+11:00

This is a live post from the Arizona Ontology Conference, hosted by the department of philosophy at the University of Arizona and organized by Laurie Paul and her assistant Sara Bernstein. Thomas Hofweber is currently defending his "Ambitious Yet Modest Metaphysics", which attempts to explain how to do ontology without deferring completely and reverently to the sciences and without embracing the special technical notions from metaphysics.

Earlier in the conference. Brian Weatherson offered a view prescribing that we not explain causative relations (e.g., those expressed by 'opened', 'killed', 'broke', 'saved', etc.) in terms of causation but rather explain causation in terms of such causative relations. The disjunctive account says that c causes e iff either (1) e counterfactually depends on c or (2) an agent of c stands in a causative relation to an e state. There was much discussion about how to demarcate the class of causatives, including persuasive commentary from Elizabeth Barnes.

Hilary Greaves gave us an education in physics while defending a paper that she co-authored with Frank Arntzenius. The paper explores some of Richard Feynman's ideas in the context of a recent debate about time reversal in classical electromagnetism.

Andy Egan argued that disputes about taste hang on self-attributions of dispositional properties. The function of disagreements about taste is to get one's interlocutor to self-attribute such properties. The thesis was to explain why disputes about taste are defective (when they are defective) in terms of this key role played by taste claims.

The after dinner talk last night was given by Robin Jeshion She argued that, in the context of naive realism, descriptivism can't work since it does such a lousy job at capturing spatial representational content.

More to come, including pictorial evidence of the festivities.

"God bless us, every one!"

2007-12-22T23:24:00.000+11:00

Berit says I should get my ass back on my blog. So here's the update. Christmas in Jersey with the family. There are rumors of a reunion with the Brooklyn side. They usually like to add a little coffee to their sambuca, so I expect it to be colorful. Giving commentary about intuitionistic truth at the APA. Will post on that soon. Looking forward to catching up with friends in Baltimore, although I'll be pretty busy with my department's metaphysics hire. May spend some time in NY and then off to Tucson for what I expect to be a very intense ontology conference. Berit and I will ride horses across the desert in the rain and discuss our counterfactual theory of essential properties.

ANU offers to Schellenberg and Southwood

2007-12-06T11:01:00.000+11:00

ANU recently delivered offers to Susanna Schellenberg (Pittsburgh) and Nicholas Southwood (ANU).

Schellenberg currently holds a postdoc at ANU. Her paper "The Situation-Dependency of Perception" is forthcoming in JPhil and "Action and Self-location in Perception" appeared in Mind. Her book in progress is titled, Perception in Perspective.

Southwood currently holds a postdoc at ANU and was a Fulbright Scholar at Princeton University. His book Contractualism and the Foundations of Morality is forthcoming with OUP.

With the recent hire of Jonathan Schaffer, acceptances from Schellenberg and Southwood would really add to the strength of the department.

UPDATE: Schellenberg and Southwood have accepted.

Mindpapers

2007-11-18T11:36:00.000+11:00

Dave Chalmers and his assistant editor, David Bourget, have launched Mindpapers, which is a bibliographic database of over 13,000 papers in the philosophy of mind. Dave discusses the new tools over at Fragments---among them, highly flexible search options and statistical information. For instance, based on Google Scholar data, we find the top 100 most cited works in Mindpapers.

Here are the top 10 most cited by philosophers:

1. [3060] Jerry Fodor (1983). The Modularity of Mind. (More) [7.2b. Modularity]

2. [2608] Daniel Dennett (1991). Consciousness Explained. (More) [1.4c. Dennett's Functionalism]

3. [2469] Gilbert Ryle (1949). The Concept of Mind. (More) [4.3a. Logical Behaviorism]

4. [1974] Saul Kripke (1972). Naming and Necessity. (More) [1.3c. Kripke's Modal Argument]

5. [1750] David Chalmers (1996). The Conscious Mind: In Search of a Fundamental Theory. (More) [1.1a. Consciousness, General Works]

6. [1612] Daniel Dennett (1987). The Intentional Stance. (More) [2.1b. The Intentional Stance]

7. [1451] Jerry Fodor (1975). The Language of Thought. (More) [2.1a. The Language of Thought]

8.[1388] Jon Barwise & John Perry (1983). Situations and Attitudes. (More) [2.3a. Information-Based Accounts]

9. [1266] Jerry Fodor & Zenon Pylyshyn (1988). Connectionism and cognitive architecture. (More) [6.3a. Connectionism and Compositionality]

10.[1257] John Searle (1980). Minds, brains and programs. (More) [6.1c. The Chinese Room]

Here are the top 10 most cited overall:

1. David Marr (1982). Vision. Freeman. (Cited by 5170 | Google | More links | Annotation | Edit) [7.4d. Levels of Analysis]
Defines computational, algorithmic and implementational levels.

2. James Gibson (1979). The Ecological Approach to Visual Perception. Houghton Mifflin. (Cited by 4886 | Google | More links | Edit) [7.2e. Embodiment and Situated Cognition]

3. Antonio Damasio (1994). Descartes' Error: Emotion, Reason, and the Human Brain. Putnam. (Cited by 4670 | Google | More links | Edit) [5.1c. Emotions]
Additional links for this entry:

4. Daniel Kahneman, Paul Slovic & Amos Tversky (eds.) (1982). Judgment Under Uncertainty: Heuristics and Biases. Cambridge University Press. (Cited by 3476 | Google | More links | Edit) [7.2d. Rationality]

5. Jerry Fodor (1983). The Modularity of Mind. MIT Press. (Cited by 3060 | Google | More links | Annotation | Edit) [7.2b. Modularity]
Perception happens in informationally encapsulated, domain-specific modules. Central systems aren't encapsulated, and so may be impossible to understand.

6. Edwin Hutchins (1995). Cognition in the Wild. MIT Press. (Cited by 2764 | Google | More links | Edit) [2.4h. Collective Intentionality]

7. Terry Winograd & Fernando Flores (1987). Understanding Computers and Cognition. Addison-Wesley. (Cited by 2756 | Google | More links | Edit) [6.6. Philosophy of AI, Misc]

8. Daniel Dennett (1991). Consciousness Explained. Penguin. (Cited by 2608 | Google | More links | Annotation | Edit) [1.4c. Dennett's Functionalism]
Argues against the "Cartesian Theatre", advocating a "multiple drafts" model of consciousness. Presents a detailed model of processes underlying verbal report, and argues that there is nothing else (e.g. qualia) to explain.

9. Mihaly Csikszentmihalyi (1990). Flow: The Psychology of Optimal Experience. Harper & Row. (Cited by 2522 | Google | Edit) [8.3j. The Stream of Consciousness]

10. Gilbert Ryle (1949). The Concept of Mind. Hutchinson and Co. (Cited by 2469 | Google | More links | Annotation | Edit) [4.3a. Logical Behaviorism]

How do they compile such a massive resource...you ask? Apparently, the software harvests JSTOR and other archives and personal websites for papers, and recognizes and parses bibliographic information. Then if the program determines that the entry is highly likely relevant to Mindpapers, it is automatically categorized based on further Bayesian programming. The statistical information is automated as well. Pretty cool!

Ruth Barcan Marcus Wins Lauener Prize

2007-11-13T01:34:00.000+11:00

The Lauener-Stiftung announces that the Lauener Prize for an Outstanding Oeuvre in Analytical Philosophy 2008 goes to Ruth Barcan Marcus (Reuben Post Halleck Professor of Philosophy, Emeritus, at Yale University).

The 3rd International Lauener Symposium on Analytical Philosophy held in honour of Ruth Barcan Marcus will take place in 2008 in Bern, Switzerland.

HT: Leiter

Arizona Ontology Conference 2008

2007-10-24T17:01:00.001+10:00

Speakers Include
Berit Brogaard, ANU
Andy Egan, Michigan
Adam Elga, Princeton
Hilary Greaves, Rutgers/Oxford
Thomas Hofweber, UNC-Chapel Hill
Jenann Ismael, Arizona/Sydney
Robin Jeshion, UC-Riverside
John MacFarlane, UC-Berkeley
Daniel Nolan, Nottingham
Jill North, Yale
Josh Parsons, Otago
Joe Salerno, ANU/Saint Louis
Brian Weatherson, Rutgers

Conference Announcements

2007-10-21T18:00:00.000+10:00

The Epistemology and Methodology of Jaakko Hintikka
a symposium
Roskilde University, Denmark
November 16-17, 2007

Speakers include
* Adam Didrichsen
* Vincent F. Hendricks
* Jaakko Hintikka
* Stig Andur Pedersen
* Ahti-Veikko Pietarinen
* Robert Stalnaker
* Frederik Stjernfelt
* Tim Williamson

Ontological Commitment Conference
Hosted by the Centre for Time
University of Sydney
November 30 - Dec 1, 2007

Speakers include
* Berit Brogaard (Missouri/ANU)
* Mark Colyvan (Sydney)
* Uriah Kiegel (Arizona/Sydney)
* Kristie Miller (Sydney)
* Luca Moretti (Sydney)
* Jonathan Schaffer (ANU)
* Amie Thomasson (Miami)

The first annual Midwest Epistemology Workshop
Northwestern University
November 30-December 1, 2007.

Speakers include
* Ernie Sosa
* Robert Audi
* Al Casullo
* Richard Fumerton
* Sandy Goldberg
* John Greco
* David Henderson
* Jennifer Lackey
* Matt McGrath
* Baron Reed.

Btw, the latest issue of The Reasoner is now online.

Conditionals at Konstanz

2007-10-18T13:48:00.000+10:00

View Larger Map

First Formal Epistemology Festival
Conditionals and Ranking Functions
at Konstanz University, July 28-30, 2008
Call for Papers here.

Special Issue of Erkenntnis
Conditionals and Ranking Functions
Guest editors: Franz Huber, Eric Swanson, and Jonathan Weisberg.
Call for submissions here.

Formal Epistemology Postdoc Positions
Project: Belief and Its Revision
1/2008 to 12/2012

Copenhagen Conference Pictures

2007-10-13T01:42:00.001+10:00

1st Synthese Annual Conference

Pics by Brit Brogaard, Vincent Hendricks, Fenrong Liu and Joe Salerno

Lewis Conference (Day 3)

2007-10-12T14:41:00.000+10:00

Day 3 of the conference began with an animated talk by Alan Hájek on whether formal methods are a boon or bane for philosophy. He also discussed whether we should be doing traditional epistemology or Baysian epistemology. He argued both sides of both issues, and then painted Lewis' intellectual history as a synthesis of the two sides of these two disputes. It was quite a treat.

Great talks were also given by Ulrich Meyer, Vladan Djordjevic, and Rohit Parikh.

Photos to come, but a small sample appear over at Lemmings.

Lewis Conference (Day 2)

2007-10-04T22:59:00.000+10:00

The talks today were on the semantics for conditionals. John Cantwell proposed a branching-time framework that aimed to unify our understanding of indicative and subjunctive conditionals. The variation in truth-value of corresponding indicative and subjunctive "Oswald sentences" is, on John's view, to be explained without positing a plurality of conditionals. The job can be done by tense and our understanding of open futures.

Hannes Leitgeb offered a probabilistic semantics for subjunctive conditionals. His very precise proposal (which I won't go into here) is a version of the thought that subjunctives are true just in case the consequent is sufficiently likely (in some objective sense) given the antecedent. By default Hannes rejects the strong and weak centering assumptions---respectively,

(A & B) --> (A []--> B), and

(A []--> B) --> (A --> B)

What this means is that, unlike the standard semantics, we get the desirable outcome that the truth of A and B is not sufficient to imply a counterfactual dependence between A and B, and that the truth of A and ~B is not sufficient to undermine a counterfactual dependence between A and B. The actual world can be one of the exceptional worlds where what does occur is not highly likely to occur (and where what is highly likely to occur does not occur).

Hannes replaces the centering assumptions with weaker centering-like assumptions---viz.,

(T []--> (A & B)) --> (A []--> B), and

(A []--> B) --> (T []--> (A --> B))

I believe T is meant to be a tautology, and so, the following rough paraphrase can be given: the truth of A & B does entail A []--> B, when A & B is sufficiently likely on its own, and the truth of A & ~B entails the negation of A []--> B, when A & ~B is sufficiently likely on its own. Perhaps we can put it in something like Lewisian terms. The stronger of the two says that no world is as close to the actual world as are the very likely worlds; and the weaker thesis is that no world is closer to the actual world than are the very likely worlds.

Photos:

1. Statue

2. John Cantwell

3. Hannes Leitgeb

4. Niels Bohr Mansion

Lewis Conference (Day 1)

2007-10-04T01:37:00.000+10:00

Today began the 1st Synthese Annual Conference, Between Intuition and Logic: David Lewis and the Future of Formal Philosophy, which was hosted at the Honorary Niels Bohr Mansion in Copenhagen and organized by Johan van Benthem, Vincent Hendricks and John Symons.

John Collins started things off with his paper "Formal and Informal Models of Belief", in which he embraced a Lewisian theory of knowledge:

if S knows that X, then there is no uneliminated possibility that is very close to actuality and in which X is false.

He argued, among other things, that the threat of skepticism is not as ubiquitous as Vogel and Hawthorne suggest. The statistical information that n number of otherwise healthy people die of a heart attack is not enough to make the world in which i die of a heart attack very close to the actual world. That's because people don't just die of heart attacks if absolutely nothing is medically wrong with them. Since the actual world is not one where unbenownst to me there is something wrong with me, there is no very close world where I am one of the unlucky few to die in this way. So, my original ordinary knowledge claim about where I'll be tomorrow still stands. Of course, if it turns out that unbenownst to me and my doctors there is something medical wrong with my heart, then my ordinary knowledge claim falters.

Allesandro Torza gave the most formal of the talks thus far, titled "How to Lewis a Kripke-Hintikka". He argued that BL (i.e., [quantifier] independence friendly modal logic) is more expressive than QML (quantified modal logic); there are modal notions (e.g., the notion of rigidity for general terms) that can be expressed by BL but not by QML. However, this portion of BL cannot be translated into counterpart theory, and so, there is reason to doubt that counterpart theory is adequate to model our modal intuitions.

Brit and I gave a version of our paper "Remarks on Counterpossibles", in which we motivate and defend a modified version of Daniel Nolan's impossible worlds account of counterpossible conditionals.

Laurie Paul argued that the trumping examples, which have forced Lewis to give up his old theory of causation (see Schaffer's famous paper) do not obviously show what they were intended to show. The thrust of the objection was that until we clarify what it is to "interrupt a causal process", it is unclear how to interpret the trumping examples. The military handbook tells us that a Major's orders trump the Sgt.'s orders, but how do we get from there to a case of *causal* trumping? Merlin's (and not Morgana's) spell is stipulated to be the consequential of the two spells. But how do we get from there to Merlin's, but not Morgana's, spell caused the outcome?

David Lewis Conference

2007-09-22T21:57:00.000+10:00

SYNTHESE ANNUAL CONFERENCE

Title / Between Logic and Intuition: David Lewis and the Future of Formal Methods in Philosophy

Synthese hosts its first annual conference at the Carlsberg Academy in Copenhagen, October 3- 5 , 2007. The conference is sponsored by PHIS - The Danish Research School in Philosophy, History of Ideas and History of Science and Springer.

Abstract / David Lewis is one of the most important figures in contemporary philosophy. His approach balances elegantly between the use of rigorous formal methods and sound philosophical intuitions. The benefit of such an approach is reflected in the substantial impact his philosophical insights have had not only in many core areas of philosophy, but also in neighboring disciplines ranging from computer science to game theory and linguistics. The interplay between logic and intuition to obtain results of both philosophical and interdisciplinary importance makes Lewis' work a prime example of formal philosophy. Lewis' work exemplifies the fruitful interplay between logic and intuition that is central to contemporary philosophy. This conference serves as a tribute to Lewis and as a venue for adressing questions concerning the relationship between logic and philosophical intuition.

This first Synthese Annual Conference is the venue for discussing the future of formal methods in philosophy.

Invited Speakers
John Collins, Alan Hájek, Hannes Leitgeb, Rohit Parikh and L.A. Paul

Speakers
Berit Brogaard and Joe Salerno, John Cantwell, Vladan Djordjevic, Ulrich Meyer, Neil Tennant

Program Committee and Conference Chairs
Johan van Benthem, Vincent F. Hendricks, John Symons (SYNTHESE) and Stig Andur Pedersen (PHIS)

Conference Manager
Pelle Guldborg Hansen

Registration
Please write conference manager Pelle Guldborg Hansen to register:

Department of Philosophy and Science Studies
Roskilde University, P6
P.O. Box 260
DK4000 Roskilde, Denmark
Phone: (+45) 4674 2540
Cell: (+45) 2334 2175
Fax: (+45) 4674 3012
Email: pgh@ruc.dk

A conference fee is to be paid cash upon final registration (Wednesday, October 3, 2007). The conference fee is 150,00 Danish kroner a day, thus participation for the entire duration of the conference (Thursday, October 3 – Saturday 5, 2004) is 450,00 Danish kroner. The conference fee covers the lunches with free beverages, conference booklet, tea and co¤ee during the breaks. NOTICE: Please remember exact amount. Deadline for registration Monday, October 1, 2007. If email is used include ‘SAC 2007’ in the subject entry. All questions pertaining to registration and accommodations should be directed to Pelle Guldborg Hansen.

Conference Website:

http://www.springer.com/west/home/philosophy?SGWID=4-40385-70-35761018-0

Academic Satire by Emily Beck Cogburn

2007-09-22T17:09:00.000+10:00

The Breaking of Things is a novel by Emily Beck Cogburn. The story is told from the point of view of an overweight male philosophy professor stuck in a dead-end job in Louisiana. Below is an excerpt from Chapter 1, which is available in its entirety here.

... The rest of the philosophy faculty ignored Brady’s tantrum. Near the door, two men whispered together, their desks almost touching. One had a long Santa Claus beard, but his mad-scientist eyebrows and skeletal frame would have frightened the bravest of children. The other man’s distorted face looked like it had been shaped from modeling clay by a careless child. I wondered if the obstetrician had used forceps to pull him out of his mother. He leaned forward and said something in a French accent. Santa Claus stroked his beard and answered inaudibly.

Directly in front of the whisperers, a short, trim Indian man stood and walked across the room to the windows. He grabbed the sash and pulled up. The window didn’t budge, but he kept trying, grunting each time he yanked on it. Even from across the room, I saw his forehead vein bulge from the exertion. I expected him to break the glass with his fist, or maybe throw a chair through. “Sack of shit janitors,” he muttered, returning to his seat.

After glancing around to make sure no one was watching, I slipped off my tie and hid it under the campus newspaper. Just as I unfastened the top button of my shirt, Richard Matthews, the Chair of the department, looked over at me. I feigned a stretch and smiled, and he quickly went back to shuffling through a folder of papers. My first day on campus, Matthews had introduced himself and then stood there, as though waiting to take my order. Restraining myself from saying, “I’ll have a cheeseburger and a Coke, please,” I’d talked inanely about how I loved Louisiana so far. He’d nodded, finally shuffling off when the secretary called him.

The only other person I could positively identify was Jane Campbell, the lone woman in the department. Sitting behind Matthews, she tapped a Birkenstock on the tiled floor and read Harper’s Magazine. Her gray hair was cut short, and she wore a dark cotton dress that reached her ankles. She glanced at her watch, shaking her head as though she’d long ago become resigned to this kind of irritation.

I leaned forward and pulled at the back of my shirt, trying to let in some air. Sweat dripped from my scalp and ran down my face like tears. I was trying to remember if I’d ever felt hotter when someone said, “Don’t panic until they start handing out the soap.”

I laughed, the noise echoing in the quiet room. Here we were, effectively trapped in a steaming room, waiting for something. Was the university administration planning to gas the whole philosophy department? Get rid of the undesirables?

The silence grew more pronounced as Santa Claus and the Frenchman stopped whispering. Six philosophy professors looked at me as though I’d broken a sacred pact. I slid down in my chair as much as my bulk would allow, trying to disappear.

The joker lifted his desk by its arms and turned it until he faced me. I wondered why I hadn’t noticed him before. He wore wire-rimmed glasses and a yellowing dress shirt. He wiggled the bare toe sticking out of his canvas sneaker and assessed me for a few seconds. “After class, Miller.” Smiling conspiratorially, he returned his desk to its original position.

The other faculty gradually returned to their diversions. The last one to stop staring at me was the Indian man. If he’d been a cartoon character, smoke would have been coming out of his ears.

Forcing myself to look away, I picked up The Daily Crawfish. The main article was a list of tips for incoming freshman: wear both straps of your backpack, leave your tube tops at home, and take notes in every class. Good advice all around, I thought. In this heat, I could almost understand the tube tops, but the thought of exposing that much of my flabby midriff was frightening. This summer, I’d started wearing a T-shirt while swimming. Diet starts tomorrow, I reminded myself. No more cheeseburgers.

The Indian man grumbled and fanned himself with a yellow folder. I was sure the sweat stains under my arms had met in the middle of my back. As I contemplated unfastening another button on my shirt, two overweight women in cheap suits entered the classroom. Holding cardboard boxes, they flanked the door while a tall, lanky man entered. Everyone stood up. I tried, but only managed to crush my gut against the desktop.

The man wore an obviously expensive suit that provided an arresting contrast to his polka dot bow tie and goofy smile. He waved his hand to indicate that we should sit. As he strode toward the front of the room, he nodded to Matthews, but said nothing. I wondered if he remembered our Chair’s name. Behind the lectern, he surveyed the sweating philosophers.

“My friends,” he began, “as President of Louisiana A&M, I wanted to come and show my gratitude in person for all the great work you do here. It is very important to me to meet you in small groups like this. To meet you all and know those who work so hard to make this institution what it is.

“Too often administrators don’t show their appreciation to the faculty. We think we are too busy to make the little gestures that mean so much. You all work hard. Today I want to give credit where credit is due. I want each of you to realize how important you are. The classes you teach enlighten our youth— our future! Your research ennobles us all. You are what this is all about. Without faculty, what is a university? Just a bunch of buildings.

“Nothing I can do for you is too much. Whatever I do will be too little. But today I just want to make a small gesture of my appreciation. Psychology is a very important subject.” At this point one of the women set down her box, came a few steps closer and staged-whispered, “Philosophy.”

“Philosophy. Of course,” the president continued. “Always been one of my favorites. And we have a first-class department here. You are all doing a bang-up job. I say, keep up the good work! Keep thinking! And here’s to that.”

He nodded and watched, smiling, as the women distributed a shiny apple to each of us. “May they give you energy to pursue the truth,” he said as he left. His entourage trailed behind like two dowdy bridesmaids. ...

Links and Photos

2007-09-12T21:23:00.000+10:00

Duncan Pritchard has posted most of the papers and commentaries from the Social Epistemology Conference held at the University of Stirling.

Still waiting on Declan Smithies' photos from the Value of Knowledge Conference held at the Vrije Universiteit Amsterdam.

PHIBOOK - The Yearbook for Philosophical Logic now has a web presence.

Among my favorite philosophy blogs is Jon Cogburn's. Here's a recent dark post about the philosophy job market for newbies.

In case you haven't seen the Philosophy Journal Information wiki go here. Includes info on editorial practices, response times, backlogs on publishing, policies on providing comments to authors, etc.

...and last but not least, some photos from a party at Declan Smithies' bitchin' crib.

Philosophical Progress (Bryan Frances)

2007-09-09T12:13:00.000+10:00

Intelligent, smart-assed, freshman will often say, in class, that philosophy never settles anything or answers any questions. This is a good challenge, I think. I tell them that it’s easy to prove that there is tremendous philosophical progress. Moreover, I claim that they will experience it for themselves over the next fortnight, for that is all the time it takes for the proof.

I start my freshman course by going over epistemological concepts. After several centuries of experience, I know that in their minds ‘knowledge’, ‘belief’, ‘evidence’, ‘justified’, ‘true’ and related concepts form one big messy conceptual structure. They form one big blob. After two weeks, the blob has taken form: there are now several blobs, and they have some idea how the blobs may be related. It’s as though things are starting to come into focus; there are many more pixels per square inch. I don’t care what anyone else says: this is genuine and personally significant philosophical progress.

I tell them about John Madden. He was the head couch of the Oakland Raiders football (American) team for many years. Then he became a “color” commentator. He started out using terms like ‘force’, ‘momentum’, and ‘energy’ pretty much as synonyms. Then some incredibly geeky physics types wrote him letters and tried to straighten him out on how those are different concepts and are related in certain interesting ways. (This was back when I actually watched TV, especially sports.) He tried to mend his ways, presenting his new understanding on the air like a brave soul.

Something similar happens in students in a philosophy course. I don’t care what anyone else says: this is genuine and personally significant philosophical progress.

I remember talking with Adam Pautz when he was an undergraduate at Minnesota (he’s now an excellent philosopher at Texas). I was a graduate student and he wanted to diss David Lewis a bit. He accosted me in the hallway and started to talk about the feebleness of David Lewis’s system of laws, counterfactuals, possibilia, etc. I was blown away of course; how can an undergraduate at Minnesota be so fucking smart and well read? I tried to defend Lewis by saying that he had the virtue of showing how many seemingly disparate concepts are really related in fascinating ways. If I remember right, Adam thought this was an interesting response.

There are other forms of philosophical progress. For one thing, there are good questions that only philosophical reflection reveals. Who would have thought of the all the good questions regarding truth, vagueness, and material constitution without the liar, sorities, tibbles, and statue-clay paradoxes? In these cases philosophy reveals problems that science and other intellectual pursuits miss entirely.

I personally think that these forms of progress are tremendously valuable. But what other forms of philosophical progress are there? Maybe things of the form: if you buy into theses X, Y, and Z, then the arguments and evidence say you should also accept theses A and B.

But is there more than this?

Expressivism Conference Photos

2007-09-02T00:30:00.000+10:00

Expressivism, Pragmatism and Representationalism Conference 2007

Update: Chalmers has thoughts about the conference here, and more pics here, and Brit has pics here.

Expressivism, Pragmatism, and Representationalism

2007-08-29T21:47:00.000+10:00

Busy conference season in Australia. Today ends the Evolution and Cooperation Conference at ANU, organized by Richard Joyce & Kim Sterelny.

Speakers:
Steve Downes (University of Utah); Christian List (LSE); Ben Kerr (University of Washington); Timothy Ketelaar (University of New Mexico); Matteo Mameli (Cambridge); Fiery Cushman (Harvard); Peter Godfrey-Smith (Harvard); Kai Spikerman (LSE); Brett Calcott (ANU)

Day 1 included Christian List, who had neat empirical data on the Condorcet jury theorem as applied to deliberative democracy. Another great talk was Fiery Cushman's, which included loads of data about our judgments regarding moral consequences and intentions. And there were others.

Ah, I took my first spin around the block on the left side of the road. It was at night, and some street signs were apparently missing, but overall the episode went down without a hitch. Driving on the left is easier than I thought. Just take everything you do with your left hemisphere and replace it with everything you do with your right hemisphere, and vice versa. The drive was in part preparation for my trip to Sydney for the Expressivism, Pragmatism and Representationalism conference, hosted by the Centre for Time. I didn't drive to Sydney (Chalmers and Fish took care of business), but I did get stuck with the honor of driving around to find a parking spot in Potts Point. No problemo, but I think i'll stay on my bicycle for a while.

Arrived during Simon Blackburns talk. He waxed broadly about the ins and outs of expressivism. Also caught Jamie Dreier's talk on the difference between irrealism and realism, and the pitfalls of trying to articulate said difference. This was also our 3 and a half year old daughter's first time attending philosophy talks. She had a blast. She wanted to know what order-of-explanation has to do with the reality of the subject matter. Will check out more talks tomorrow. Still don't know how long we are staying in the fabulous city, but won't be upset if we leave later rather than sooner.

Most Counterfactuals are False

2007-08-28T00:22:00.000+10:00

The title is of Alan Hájek's very interesting paper, which can be found on his website. I mentioned the main argument in a post last January:

1. 'Might' and 'Would' are dual operators. So "If A were the case, B might not be the case" entails "It's false that if A were the case B would be the case":

2. Indeterminism (in particular, chanciness) and indeterminacy (in particular, vagueness) in all the interesting cases underwrite a 'might not' claim. For instance, any chance of both A and not-B (no matter how small) underwrites the 'might not' claim, viz., "If A were the case, B might not be the case":

Hence, in all the interesting cases, its false that if A were the case B would be the case. So most (uttered) counterfactuals are false.

Alan rejects the contextualist response, but I won't develop his arguments. I'll just mention here what I think the contextualist should say. Counterfactuals are context sensitive. Whether apparently bizarre {A, not-B} possibilities are sufficiently close depends on the context. In conversational contexts that involve discussion of quantum indeterminacy, etc., such possibilities are relevant and close. Hence, the would-claim, , is false. But in ordinary conversational contexts, the apparently bizarre {A, not-B} possibilities are irrelevant and remote. Hence, the might-claim, , is false. In neither context is both and true. Luckily for us and the would-claims we ordinarily use, quantum indeterminacy is rarely seriously entertained.

Reasons, Reasoning and Rationality

2007-08-23T22:16:00.000+10:00

Today at ANU concluded the conference on Reasons, Reasoning and Rationality, Themes From the Work of John Broome. Speakers: Jamie Dreier (Brown), Nic Southwood (RSSS), Andrew Reisner (McGill), Geoffrey Brennan (RSSS), Garrett Cullity (Adelaide), Daniel Star (CAPPE), Wlodek Rabinowicz (Lund), John Broome (Oxford). I won't try to do justice to all of the interesting papers, but instead will touch on a couple.

Jamie Dreier examined tensions between various formulations of two principles, which he aimed to reformulate and vindicate:

(Buck-Passing) For something to be good is for it to have properties that provide sufficient reason to choose, prefer, ... or admire it.

(Subjectivism) R is a reason for S to Phi iff R explains why Phi-ing promotes something S wants.

We had the most fun thinking about the Narcissus Bomb Example:

Philosopher chemists at Washington University have invented a Narcissus Bomb. Once triggered, this bomb will explode unless it is in the presence of someone who admires it enormously. You are now in the presence of a triggered Narcissus Bomb and nobody else is in the room.

This part of the talk was designed to show the limitation of Buck-passing. The explosive potential of the bomb is sufficient reason to admire it, but the bomb is evil. Jamie relied here on a fix by Nomy Arpaly, which hypothesizes that the bomb is sufficient reason to make it the case that you admire it but not reason to admire it.

I don't know yet how to think about reasons, but arguably a reason for Phi-ing is a reasoning Psi-ing when Phi-ing entails Psi-ing. But then since 'makes it the case' is factive, 'making it the case that you admire the bomb' entails 'you admire the bomb'. Hence, by the above closure principle, a reason for the former is a reason for the latter, and we're back to the original problem.

Another exciting paper was by Wlodek Rabinowicz, in which he argued Incommensurability is possible if there is vagueness. Incommensurability obtains when two thing x and y are such that neither is better than the other, yet they are not equally good. Wlodek was responding to an argument that Incommensurability is not possible. The argument depended on the following symmetry claim: if it is indeterminate that x is better than y then it's indeterminate that y is better than x.

Berit had a great counterexample to symmetry. Consider: x seems to have the temperature absolute 0. It's determinate that y doesn't seem colder than x, because on all sharpenings of the vague predicate 'seems absolutely cold' it is true that y doesn't seems colder than x. After all, y can't seem colder than absolute 0. But it's indeterminate that x seems colder than y, because on some sharpenings of the predicate 'seems absolutely cold' y doesn't seem absolutely cold. Hence, symmetry fails.

Objects and Arrows

2007-08-19T14:54:00.000+10:00

Objects and Arrows is a new blog by John Symons, editor-in-chief of Synthese. The blog provides updates from the frontier on emergence, epistemology, philosophy of psychology and related matters.

On to Oz

2007-08-14T11:10:00.000+10:00

Today Berit and I enjoyed our first full day at Australian National University. We got a little work done in the morning, listened to Wlodek Robinowicz' very interesting talk, "Dutch Books Against Groups and Jury Voting", which as you might surmise was about exploitation strategies against rational subjects in betting and jury situations. Lessons were drawn about the limitations of betting interpretations of probability. Then we met more of the department and its visitors over the traditional afternoon tea on the outside balcony. The sounds of the local birds are pretty amazing. I expect soon to walk with my daughter to the nearby hills where the kangaroos are rumored to run rampant.

Sieg's Survey

2007-07-28T02:33:00.000+10:00

As Gregory Wheeler notes at Certain Doubts, Wilfried Sieg, Christian Schunn and Melissa Nelson are conducting a survey for those teaching introductory logic courses. It's part of project investigating the effectiveness of different ways of teaching such a course. I just took the survey and it consumed only a few minutes of my time.

Oswald was Indeed CIA!

2007-07-21T05:28:00.000+10:00

I just stumbled on a couple of interesting declassified documents floating around the internet, and I couldn't resist sharing them with my readers. The first was written by the director of the CIA in 1964 and asserts that Lee (Harvey) Oswald did recon for the agency in the late 50s and reveals in the last paragraph that Oswald's famous 1959 "defection" to Russia was an agency assignment. Oh, that's nice. So when exactly was Oswald NOT on assignment?

The second document includes an attached 1947 memo that links Oswald's assassin Jack Ruby (formerly, Jack Rubenstein) to Congressman Richard Nixon as an informant of some sort. WTF?

Don't know when these docs were declassified or even if they are authentic, but here they are.

UPDATE: Here's a blog devoted to questions about the authenticity of the first document, also known as the McCone-Rowley Document.

Reasoner 1(4)

2007-07-21T04:40:00.000+10:00

The fourth issue of the Reasoner is now available online. Here are the contents:

Interview with Brendan Larvor
David Corfield
Conceivability, Possibility and Counterexamples
Anand Jayprakash Vaidya
A Counterfactual Account of Essence
Berit Brogaard and Joe Salerno
Knowledge, Truth and Justification in Legal Fact Finding
Déirdre M. Dwyer
The Principle of Agreement
John L. Pollock
A Note on Kripke's Puzzle about Belief
Christian Constantinescu

Oneness

2007-07-12T17:38:00.000+10:00

Today Knowability turns one. We've had just under 20,000 visits, 14,000 uniques (first timers or those returning after an hour), and 8,000 first time visitors (based purely on a cookie). Contributions have been made by guest authors, Bryan Frances and John Greco, and much support was received from Brit over at Lemmings and from other weblog administrators. Thanks guys.

Epistemology and Methodology of Jaakko Hintikka

2007-07-12T03:55:00.000+10:00

The Danish Research School in Philosophy History of Ideas and History of Science is sponsoring a Hintikka Symposium
November 16-17, 2007

Roskilde University, Denmark

Invited Speakers

* Adam Didrichsen
* Vincent F. Hendricks
* Jaakko Hintikka
* Stig Andur Pedersen
* Ahti-Veikko Pietarinen
* Robert Stalnaker
* Frederik Stjernfelt
* Tim Williamson

Program and Organizing Committee

* Vincent F. Hendricks
* Frederik Stjernfelt
* Stig Andur Pedersen

Remembering Justin D'Arcy Isom

2007-07-08T14:55:00.000+10:00

I met Justin when we were both graduate students at the Ohio State University. He received his B.A. in philosophy at the University of Texas. He traveled much of the world alone and his ordinary descriptions of the world around him were often worth more than a thousand words. This was sort of remarkable since Justin had lost his sight at the age of one to a retinal nerve cancer. What I didn't realize at the time was that Justin's overall condition would degenerate. He died on April 23, 2007.

Justin and Neil Tennant devised a braille-like proof system so that Justin could more fully participate in discussions about (intuitionistic) proofs. Neil shares his memory of Justine in the department newsletter, Logos.

Second-order logic and Gödel’s first incompleteness theorem (Frances)

2007-07-06T02:29:00.000+10:00

That’s a very impressive title for a blog entry, but I promise that things will not get very complicated in what follows. For I am no logician. I’m not even a philosopher of logic. So, I don’t know much about logic. But I know just enough to be confused about something having to do with second-order logic and Gödel’s first incompleteness theorem.

Let L be the formal first-order language with a name for zero and function symbols for the successor function, addition, and multiplication (and no other non-logical symbols). So L is a pretty simple formal language. Let N be the interpretation of L that has as its domain the set of natural numbers {0, 1, 2, …} and assigns zero to the name ‘0’, addition to the function symbol ‘+’, etc. So N is the natural way to interpret L. Arithmetic is the set of sentences of L that are true under N. So, arithmetic is a set of sentences of a formal language, where each sentence is most naturally interpreted as an arithmetic truth. This will be an infinite set.

Arithmetic counts as a theory of L because it is “closed under logical consequence”, which means that any sentence of L that is entailed by the sentences in arithmetic is in arithmetic. Arithmetic contains all its logical consequences; that’s what makes it a “theory”.

Now a theory T in language L is decidable when there is an algorithm for deciding whether any given sentence of L is a theorem (member) of the theory. So a theory T in L is decidable when there is some algorithm that when fed a sentence S of L will tell you in a finite number of steps whether or not S is in T.

Roughly put, a theory T is axiomatizable just in case everything in T is a logical consequence of some nice subset of T. The nice subset of T generates, so to speak, everything in T (just like how the central Euclidean claims generate all the truths of plane geometry). The member sentences of the nice subset are axioms of T.

The subset could be infinite! But even so it has to be nice. That means: there has to be an algorithm that when fed a sentence of L will tell you in a finite number of steps whether or not the sentence is one of the axioms. That is, the set of axioms has to be decidable.

The famous consequence of Gödel’s first incompleteness theorem is that arithmetic isn’t axiomatizable. This is surprising! You’d think it wouldn’t be that hard to write down a nice set of axioms (say, the Peano axioms) for generating all the truths of arithmetic. But it can’t be done.

Now suppose we add second-order quantifiers and variables to L. Now let arithmetic* be the set of first-order and second-order sentences of L that are true under N. Arithmetic* contains everything in arithmetic plus some more arithmetic truths (the second-order ones).

The cool thing, in my opinion, is that arithmetic* is axiomatizable. You can write down one long sentence that generates, through logical consequence, everything in arithmetic*. So when you hear someone say ‘Gödel famously showed that arithmetic isn’t axiomatizable’, you should say to them ‘Wait a damn minute buddy. First-order arithmetic isn’t axiomatizable, but second-order arithmetic is’. So you can write down just one relatively simple sentence that generates all the (first-order) truths of arithmetic—-but it will generate a whole bunch of other arithmetic truths as well, the second-order ones.

I take it that not that many non-logicians and non-philosophers of logic are aware of that result. Hopefully I’m right about it and as a consequence this blog entry is worthwhile.

But now we come to my question: why is it thought to be such a big honking deal that arithmetic isn’t axiomatizable? I take it that people who know about these things think the second-order axiomatization is not terribly significant. But why?

I guess some people are allergic to second-order logic, but I don’t know anything about that issue. What if you think second-order logic is a-okay?

Is the problem connected to this: whereas there is an algorithm that when fed a first-order sentence S of L that’s logically true, will tell you in a finite number of steps that S is indeed logically true, but there is no algorithm that when fed a second-order sentence S of L that’s logically true, will tell you in a finite number of steps that S is indeed logically true? If so, why does that matter so much?

Reasoner 1(3)

2007-06-28T04:20:00.000+10:00

The third issue of the Reasoner just hit the e-stands. Here's the TOC:

"Pierre May be Ignorant but He's Not Irrational"
Jesse Steinberg (UC-Riverside)

"Free Will and Lucky Decisions"
Gerald Harrison (University of Bath)

"United States v. Shonubi: Statistical Evidence and 'The Same Course of Conduct' Rule"
Amit Pundik (Law, University of Oxford)

"Williamson on Counterpossibles"
Brit Brogaard (University of Missouri)
Joe Salerno (St Louis University)

"Mathematical Blogging"
David Cornfield (Max Planck Institute, Tübingen)

"Does Direct Inference Require Pollock's Principle of Agreement?"
Stephen Fogdall (Schnader Harrison Segal and Lewis LLP)

"The Pirahã Language, the Language Template, and the Mind"
William Abler (Geology, The Field Museum)

Williamson on Counterpossibles

2007-06-13T10:32:00.000+10:00

Lewis/Stalnaker semantics has it that all counterpossibles are vacuously true. Non-vacuism, by contrast, says that the truth-values of counterpossibles are affected by the truth-values of the consequents. Williamson, in his Hempel Lectures, objects to non-vacuism. He asks us to consider someone who answered `11' to `What is 5 + 7?' but who mistakenly believes that he answered `13'. For the non-vacuist, (1) is false, (2) true:

(1) If 5 + 7 were 13, x would have got that sum right
(2) If 5 + 7 were 13, x would have got that sum wrong

Williamson is not persuaded by the initial intuitiveness of such examples:

... they tend to fall apart when thought through. For example, if 5 + 7 were 13 then 5 + 6 would be 12, and so (by another eleven steps) 0 would be 1, so if the number of right answers I gave were 0, the number of right answers I gave would be 1. (Lecture 3)

That's the whole argument. It isn't initially clear what the full argument is, but Brogaard and I commented on our abbreviated version of it in "Why Counterpossibles are Non-Trivial" (The Reasoner v.1, no. 1). Alan Baker's critique (The Reasoner v.1, no. 2) of our paper has prompted us to say more. Here's what we think.

Williamson's conclusion is this:

(3) If the number of right answers I gave were 0, then the number of right answers I gave would be 1.

The implicit reductio must be this: If (3) is true, then (1) and (2) are true --- contrary to what the non-vacuist supposes. For if I gave 0 right answers (in close worlds where 0=1), then I also gave 1 right answer (in those worlds). Hence, I got the sum right and wrong (in those worlds).

Williamson's abbreviated eleven-plus-one steps must be these:

(i) If 5 + 7 were 13, then 5 + 6 would be 12
(ii) If 5 + 7 were 13, then 5 + 5 would be 11
...
(xi) If 5 + 7 were 13, then 5 + -4 would be 2.
(xii) If 5 + 7 were 13, then 5 + -5 would be 1.

Getting to (3) from here, however, is trickier than Williamson supposes. The argument must be that any world where 5 + -5 = 1 is one where 0 = 1, substituting `0' for `5 + -5'. Hence,

(xiii) If 5+7 were 13 then 0 would be 1.

Therefore, if 5+7 were 13 (and I gave 0 right answers), then (since 0 would be 1) the number of right answers I gave would be 1.

The argument is unsuccessful. First, substituting `0' for `5+5' is illicit, since as Williamson himself notes the non-vacuous counterfactual is hyperintensional. Hyperintensional operators do not permit substitutions of co-referring terms salva veritate.

Incidentally, Williamson takes the hyperintensionality to be a mark against non-vacuism, because substitution is valid in more ordinary counterfactual contexts. However, we need not throw out the baby with the logically ill-behaved bath water. This sort of substitution preserves truth at every world on every standard model. Only the counterpossible context (i.e., the counterfactual context whose accessibility relation invokes impossible worlds) are hyperintensional. Our logical principles can be restricted accordingly.

A second problem for Williamson emerges in steps (i) through (xiii). These conclusions hold, if the game is to evaluate the consequent of each at deductively closed worlds where 5+7 = 13. But if there are non-trivial counterpossibles, the relevant worlds of evaluation must not be deductively closed---lest they collapse into the trivial world where everything is true.

Once we deny deductive closure, Williamson's reasoning fails. Let the following world, (W), be non-deductively closed:

(W) {5 + 7 = 13, the number of right answers I gave wasn't 1, the number of right answers I gave was 0, ... }

In contexts where W-worlds are closest, (2) is true and (1) false, as the non-vacuist predicts. For Williamson's argument to succeed, the relevant impossible worlds in which I gave 0 right answers and 1 right answer must always be closer than the relevant impossible W-worlds. This hasn't been shown. Indeed, (W) is closer to the actual world than Williamson's envisaged impossible worlds, since (W) is constituted by fewer explicit contradictions.

UPDATE: changed 'explicit' to 'implicit'

New Essays on Knowability

2007-06-12T15:00:00.000+10:00

I just updated the page for the volume that i'm editing, New Essays on the Knowability Paradox. The introduction and bibliography have been substantially revised. A contributor list and contents page has been added. I also included a link to the Appendix to Alonzo Church's "Referee Reports on Fitch's 'A Definition of Value'", which i put together with Julien Murzi. Updated my own contribution as well (Essay 3). There are links to other contributions by authors who have made their papers electronically available. Will be glad when this thing is finally published.

Philosophy and Common Sense (Frances)

2007-06-09T11:44:00.000+10:00

Not every philosophy professor takes philosophy seriously in the sense that she thinks that some purely philosophical theories that go against common sense have a good chance to be true. These philosophers respect anti-commonsensical theories, in that they admit such theories are very important in the pursuit of philosophical understanding. But they also think that there is no real chance that they are true. If you have a valid argument based not on scientific but purely philosophical reasoning, and that argument concludes with something against cross-cultural and timeless common sense, then at least one of the premises isn’t true, or so they say. It might be tremendously difficult to identify the mistaken premise, but we can start our investigation off assuming that our assumption that the conclusion is false is safe. These philosophers take philosophising seriously, of course, but they don’t take seriously the idea that purely philosophical (so not empirical, not mathematical) theories have a good chance at overthrowing parts of common sense. Here is a good sample of anti-commonsensical philosophical theories.

1. 2 + 2 doesn't equal 4. (No positive mathematical truth.)
2. No vague claims are true. (Sider and Braun 2007.)
3. There are no people. (Peter Unger.)
4. Thermometers have beliefs. (Certain information-fanatic philosophers.)
5. There are no chairs. (No non-living composite physical objects exist.)
6. Stones are not solid objects. (Inspired by Sir Arthur Eddington.)
7. No one has ever had a dream. (Norman Malcolm at one point.)
8. Cats don’t feel any pain when their paws are cut off. (Descartes.)
9. The world could not have turned out even a bit better than it actually is. (Leibnizians.)
10. It isn’t wrong to torture young children purely for fun. (No moral truths.)
11. Kant didn’t live after Descartes died. Alternatively: Nothing ever happened in the past. (Time doesn’t exist; isn’t “real”.)
12. No one has ever done anything because they wanted to do it. (Various reasons.)
13. Rocks have mental characteristics. (Idealists.)
14. There could be two wholly physical objects that during their entire existence occupied the very same space and were composed of the very same particles in the very same manner. (Some contemporary metaphysicians.)
15. Other statue-clay claims.
16. Supervaluationism stuff about true disjunctions without true disjuncts.
17. Dialethicism; true contradictions.
18. Taking one cent from a rich person can make them no longer rich. (Epistemic theory of vagueness.)
19. No one is free to do anything. (No one is free, period.)
20. No one knows anything, or much of anything. (Radical sceptics.)

I hate that attitude. I wonder: what percentage of contemporary philosophers are allergic to anti-commonsensical theories?

Talk in Aberdeen

2007-05-10T16:57:00.000+10:00

I just finished a draft of my paper "The Most General Factive Mental State Operator", which I will present on Saturday at the International Conference on Linguistics and Epistemology in Aberdeen, Scotland. Helpful comments will likely not save me in time for the talk, but may save me some future embarrassment.

Then I'm off to the University of Edinburgh (May 15) for an Epistemology Workshop, where Brit and I will present a paper on counterpossible conditionals. I also expect to crash the Adjectives Conference at St. Andrews (May 18-19).

Essential but Contingent Properties

2007-05-09T02:47:00.000+10:00

My continued existence depends on lots of things. It depends on my breathing oxygen. It depends on food, water, and my not getting run over by a bus. We might say that these things are essential for my existence, since I would not exist without them. Moreover, my relation to other people may be essential to my existence. If it weren't for my uncle Mike and his power and influence in the "family", my enemies would have iced me by now. These enemies still wait in the wings. If anything were to happen to Uncle Mike, I'd be a gonner. One other example is from Paul McCartney, who wrote, "I won't live in a world without love". There are many contingent features of the world without which one would not exist.

In philosophical circles, by contrast, we require that any essential property of a thing be a necessary property of the thing. We say that something is an essential property of x iff x has the property in every possible world in which x exists. But 'essence' is said in less strict ways in the vernacular. If the doctors need to operate immediately in order to save your life, then time literally is of the essence. This suggests that the philosophical account of essence is too strong to capture ordinary use. I noted in the previous post that Berit and I agree with Fine that the strict philosophical account is too weak, for the reason that on that account any necessity is an essential property of everything. I believe that the alternative account, proposed in the last post, handles both problems nicely. The account was this:

(1) x is essentially F iff if nothing were F then x wouldn't exist,

or semantically,

(2) all the closest worlds (whether possible or impossible) where nothing is F are worlds where x doesn't exist.

Thanks to Mike Almeida, who pointed to an objection to this account (in the comments thread of the previous post). His worry boils down to this: it follows from (2) that some essential properties are contingent properties. However, as Mike has inspired me to argue here, I think this is a virtue of the account, and not an objection. The account expressed by (2) handles both the strict philosophical, and a predominant ordinary, use of 'essence'.

The key is to note that the closeness relation widens or narrows with the conversational context; the closest worlds are ones that preserve the highest proportion of the relevant background facts at the actual world. In the typical strict philosophical context where essential properties (for whatever reason) are expected to be necessary properties, the relevant background facts are the facts about what is metaphysically possible. So, the closest worlds will be all the metaphysically possible worlds. (The exceptions are philosophical contexts in which impossibilities are sincerely entertained. See previous post.) In the ordinary, non-philosophical, contexts alluded to at the beginning of this post, the relevant background facts include, for instance, that McCartney was suicidal after the loss of a girlfriend. Hence, the closest worlds without love are worlds where McCartney kills himself. Therefore, if there were no love, McCarney would cease to exist. By (2), it follows that being loved is essential to McCartney's existence. Or consider that the background facts include that I just don't run from, or rat out, other mobsters (because I'm just that brand of Sicilian American wise guy). Then the closest worlds without protection from Uncle Mike are worlds where I'm dead meat. Yes, I could go into hiding or witness protection, but then I would no longer be the wise guy that I am. So, by the above account, it is essential to what I am that I am protected by Uncle Mike.

In sum, the traditional account of essence (in terms of what properties a thing has in every metaphysically possible world in which it exists) is both too strong and too weak. Account (2) seems to take care of these problems.

Essences and Impossible Antecedents

2007-04-25T00:59:00.000+10:00

The first issue of The Reasoner has just appeared online. Berit and I contributed a paper, "Why Counterpossibles are Non-Trivial", in which we give three reasons for rejecting a vacuous reading of counterpossibles. One reason is that a non-trivial reading facilitates an analysis of essences. While Kripke's wooden table, Tabby, is necessarily a member of the set {Tabby}, it is not essential to Tabby that it be a member of that set. Neither is it essential to Tabby that seven is prime. It is tempting to offer the following explanation. If there hadn't been sets, Tabby might still have existed; and if seven hadn't been prime, Tabby might still have existed. But this sort of explanation requires, for its non-triviality and informativeness, that counterpossibles be non-trivial and informative. At some of the closest (impossible) worlds where there are no sets (or numbers), Tabby exists. By contrast, Tabby fails to exist at all the closest worlds where there is no wood. It is essential to Tabby that he be wood, but not essential to Tabby that seven is prime. Generally, x is essentially F iff x would not have existed if nothing had been F

Lewis on Non-Trivial Counterpossibles

2007-04-17T12:26:00.000+10:00

Lewis offers a number of reasons for his, the now standard, reading of counterpossibles--viz., that they are all vacuously true. He does not take his reasons to be decisive. Let's revisit the reasons. Lewis writes,

There is some intuitive justification for the decision to make a 'would' counterfactual with an impossible antecedent come out vacuously true. Confronted by an antecedent that is not really an entertainable supposition, one may react by saying, with a shrug: If that were so, anything you like would be true! Further, it seems that a counterfactual in which the antecedent logically implies the consequent ought always to be true; and one sort of impossible antecedent, a self-contradictory one, logically implies any consequent. [Counterfactuals 24]

There are two reasons given here. The first is difficult to disagree with. An antecedent that is not really an entertainable supposition, invokes triviality. If Socrates were a potato, then, sure, anything goes! I'm down with that intuition. But this is not an objection to the position that I'm more inclined to, which says that counterpossibles are sometimes non-vacuously true (and sometimes false). Lewis' point suggests incorrectly that all counterpossibles involve an antecedent that is not entertainable. Counterlogicals, such as 'if excluded middle were invalid, then double-negation elimination would be invalid too", sometimes express non-trivial consequences of alternative logics. The sincere entertaining of such logics is something that we really can, and often do, do. That said, I share Lewis' view about non-entertainable suppositions. In sum, the position that allows for a non-vacuous reading of some counterpossibles should also allow for the vacuous reading of others.

The second reason that Lewis articulates above says that a counterfactual whose antecedent logically implies the consequent ought always to be true. That is, it ought to be that logically strict implication implies counterfactual implication. Perhaps there is a pre-semantic-theoretic intuition here. But counterpossibles are strange animals from any point of view. It shouldn't be too much of a concern if they run contrary to a pre-theoretic intuition. Moreover, putting too much weight on the intuition would be question-begging. Anyone who is convinced that there are non-trivial counterpossibles will not share this intuition about the relation between strict and counterfactual implication. Lewis seems to have ruled out in advance that there might be impossible antecedents that we sincerely entertain. For this reason, I don't think that he was considering the more interesting candidates for the non-trivial reading. The bottom line is that the Lewis intuition just isn't shared by those who take seriously the idea that some impossibilities may be sincerely entertained counterfactually.

Lewis offers an explanation for why some of us believe in non-trivial counterpossibles. He hypothesizes a mistaken need to explain why some counterpossible that we do want to assert are true and others that we do not want to assert are false. He writes,

I do not think, however, that we need to discriminate in truth value among such counterfactuals. Of course there are some we would assert and some we would not:

If there were a largest prime p, p!+1 would be prime.
If there were a largest prime p, p!+1 would be composite

are both sensible things to say, but

If there were a largest prime p, there would be six regular solids.
If there were a largest prime p, pigs would have wings.

are not. But what does that prove? We have to explain why things we do want to assert are true (or at least why we take them to be true, or at least why we take them to approximate to truth), but we do not have to explain why things we do not want to assert are false. We have plenty of cases in which we do not want to assert counterfactuals with impossible antecedents, but so far as I know we do not want to assert their negations either. Therefore, they do not have to be made false by a correct account of truth conditions; they can be truths which (for good conversational reasons) it would always be pointless to assert. [24-25]

I agree that a willingness to assert the former, but not the latter, examples is not a good reason to hypothesize distinct truth-values. Indeed, it appears to me that all four examples have the same truth-value. The context of the latter two presumably invokes the trivial world where anything goes, and the context of the former two presumably invokes non-trivial reasons for thinking that the consequents obtain in the counterfactual circumstances described. What Lewis leaves out are cases where, in fact, we do want to assert the negation of a counterpossible. For instance, it is false that if intuitionistic logic were the correct logic, then excluded middle would still be valid. This counterpossible is not merely something that we wouldn't want to assert; it is something we should want to deny! Lewis' pragmatic explanation of the desire for non-trivial truth conditions does not appear to generalize.

Synthese Deadline Approaching

2007-04-15T03:00:00.000+10:00

This is a reminder about the May 1 deadline for paper submission for the special issue of Synthese, "Knowability and Beyond", which aims to cover modal epistemic issues relevant to knowability, broadly construed. The issue will contain invited papers by Jonathan Kvanvig, Gabriel Sandu and Neil Tennant, but will also provide the opportunity for other authors to make original contributions. Submissions will be double-blind reviewed. If you have something but aren't sure whether it would be appropriate for consideration, email me.

knowability@gmail.com

Vonnegut 1922-2007

2007-04-12T14:39:00.000+10:00

Kurt Vonnegut on the purpose of life: "to be the eyes and ears and conscience of the creator of the universe, you fool"

Recent Colloquia at SLU

2007-03-26T08:49:00.000+10:00

We're having a great colloquium series at SLU this semester. On Friday Liz Harman delivered a super-interesting talk, "Does Blameless Ignorance Exculpate?", in which she argued that an otherwise epistemically blameless subject may nevertheless be morally blameworthy. Other speakers this semester include Ernie Sosa, Ernie Lepore, Berit Brogaard, Rob Koons and Steve Stich.

The Reasoner

2007-03-26T01:19:00.000+10:00

The deadline for the first issue of The Reasoner is April 15. The Reasoner is edited by Jon Williamson and "is a monthly digest highlighting exciting new research on reasoning and interesting new arguments. It is interdisciplinary, covering research in, e.g., philosophy, logic, AI, statistics, cognitive science, law, psychology, mathematics and the sciences."

Greco on Skepticism

2007-03-15T02:34:00.000+11:00

My colleague and guest author, John Greco, will be discussing Skepticism live on KALW 91.7 FM (San Francisco) Sunday March 25 at 10a.m. on Philosophy Talk. The show can be heard on other stations as well. Will attempt a link to the podcast when it becomes available.

[Update: the audio is now available here]

ANU Appointment

2007-03-07T16:20:00.000+11:00

I'm very pleased to announce that I've just accepted a visiting fellow appointment at the RSSS Philosophy Program at Australian National University. Will be there from August 2007 to August 2008, and am looking forward to spending time in that fantastic department.

Copenhagen Riots

2007-03-04T06:17:00.001+11:00

Photo by: Kristian Linnemann
A third day of rioting in Copenhagen after police repelled from helicopters, and stormed a youth center to remove its occupants. The occupants were squatters (or "left-wing activists" to use BBC's term of endearment) that have been using the building as a youth center (called Ungdomshuset) since 1982.

Photo by: Kristian Linnemann

The Christian group (Faderhuset) purchased the building in 2000 and have a court order for the eviction. The occupants vow never to leave and claim that the city had no right to sell the building while it was in use.

Protests continue throughout the city. Sympathizers protested in Germany, Sweden, Norway and Austria. The violence began in Copenhagen last December during a protest against the eviction plan.

Websites like the Anarchist Black Cross inform protesters of their rights. (Some sections in English.) An article by Indymedia about the December violence can be found here.

Safia reports from Copenhagen. Outstanding photography here.

Photo by: Safia

Left: (Danish embassy in Budapest, March 2)

[UPDATE: Videos moved here.]

[UPDATE: Protests Continued Sunday, some peaceful.]
[UPDATE March 10: Anarchist sightings and arrests, but things seem to have calmed down.]

The Scientific Revolution in Linguistics

2007-03-04T03:22:00.000+11:00

I received this from Michael Hand:

Greetings all! This year marks the fiftieth anniversary of the publication of Chomsky's *Syntactic Structures*, the founding document of "generative-transformational" linguistics (in a broad sense). This is arguably the defining moment of the scientific revolution that replaced the prescientific, crassly empiricist Saussurean-Bloomfieldian linguistics with scientific linguistics as it is even today (though admittedly linguistic theory doesn't look much like the Chomskian theory of the late fifties). Chomsky's 1959 review of Skinner's *Verbal Behavior* is usually cited as the founding document of today's "cognitive science", but a case can be made that *Structures* should be accorded a share of that honor as well (though the review is more explicit in relevant ways). For an accessible and brief account of the revolution, see the early chapters of Newmeyer's *Linguistic Theory in America*; for an extensive and sometimes hilarious account of the empiricist attempt at counterrevolution, see Harris's *The Linguistic Wars*.

A moment of silent, appreciative reflection and awe right about now would not be inappropriate.

Context of Evaluating Counterfactuals

2007-03-01T18:11:00.000+11:00

If we call a tail 'a leg', then how many legs would a horse have? It would still have four. The concepts we use to evaluate the question are our actual concepts, even if the truth of the antecedent (at a closest world w) involves (at w) a revision of our actual concepts. A principle is suggested:

(*) when we evaluate the truth of a counterfactual, the concepts employed (in drawing a path in a close world w from the antecedent to the consequent) are determined by the context of evaluation and not by the semantic facts at w.

An analogous principle is this (paraphrased from Jenkins in the comments thread to the last post):

(**) when we evaluate the truth of a counterfactual about logical principles, the logic employed (in drawing a path from the antecedent to the consequent) is determined by the context of evaluation and not by the logical facts at the relevantly close worlds.

The idea is that the logic we use to evaluate the truth of a counterfactual is our default logic (ex hypothesi, classical logic), even if the truth of the antecedent (at close worlds) requires an alternative to our default logic. (*) and (**) would seem to stand or fall together.

However, (*) is not unrestrictedly true. Consider:

(1) If 'one' meant two, then 'one plus one' would mean two plus two.

If the concepts of evaluation are held fixed, then we should insist that the consequent (i.e. 'one plus one' means two plus two) is false in the closest worlds where the antecedent is true. And so, we should insist that (1) is false. But, (1) is prima facie true. Therefore, (*) is prima facie false as a general principle.

We should then expect that (**) likewise fails as a general principle. It had better fail. Otherwise we cannot engage non-vacuously, when we consider what (logical) principles would be the case if others were not. The reason we can in fact engage non-vacuously about such matters is this. When we evaluate counterfactuals about logical principles, the logic at the closest worlds is relevant to---indeed, is essential for---a proper evaluation of the consequent.

How is Modal Knowledge Possible?

2007-02-24T14:35:00.000+11:00

If They Had No Tails...
In Chapter 5 of Williamson's manu The Philosophy of Philosophy we find a proposed answer. To know that it is metaphysically necessarily that A, one needs no more than whatever it takes to know that not-A counterfactually implies a contradiction. And this requires nothing over and above the cognitive faculties employed to acquire ordinary knowledge about the empirical world. Therefore, if (metaphysical) modal knowledge---indeed, if philosophy---is possible at all (and we suppose it is), then it requires no special cognitive faculties over and above what is required for ordinary knowledge of the world. Let's focus on the purported connection between modal and counterfactual knowledge.

Williamson demonstrates that modal claims are logically equivalent to some counterfactual claims. A necessary proposition is one whose negation counterfactual implies a contradiction, and a possible proposition is one that does not counterfactual imply a contradiction. Respectively,

(1) □A (¬A □→ ⊥)

(2) A ¬(A □→ ⊥)

The lessons, according to Williamson, are these: (i) Having what it takes to understand □→ and ¬, implies having what it takes to understand and □, and (ii) modal thinking is a special case of counterfactual thinking.

I take it that (ii) is meant to entail (i)---or is equivalent to it. So there is a natural objection here. Understanding A (or grasping its meaning) is not closed under logical consequence. If A is logically equivalent to B, s may grasp A without grasping B, because B embeds concepts that s doesn't understand---e.g., 'A' is equivalent to 'A or A', and though s understands the former, he doesn't understand the latter because he doesn't grasp the meaning of 'or'. Hence, (i), and so (ii), is false, and we lose the argument for thinking that an epistemology of counterfactuals will give us everything needed for an epistemology of modality. Carrie Jenkins expresses a version of the concern over at Long Words.

I don't think the objection hits Williamson. We need to read him as offering an account of how modal knowledge is possible for beings like us, and not as defending the empirical thesis that our modal and counterfactual knowledge covary. Whether or not our knowledge of necessity and possibility does (or must) take a detour through counterfactual knowledge, is not the question. The epistemological claim is that beings like us, who are in a position to know the right-hand side of the equivalence, are also in a position to know the modality on the left. After all, we might infer the left from the right.

Here's a different objection. It is one that I think is more serious than Williamson suggests. Williamson's proof of the first equivalence requires a certain theory about how to handle counterpossibles (i.e., counterfactuals with impossible antecedents). He sides with Lewis that we should treat them as vacuously true. If this is right, then necessary implications entail counterfactual implications:

(3) □(A → B) (A □→ B)

(3) underwrites Williamson's proof of (1). If this choice about how to handle counterpossibles is a mistake, then things unravel for Williamson's epistemology of modality. For a genuine counterexample to (3) can be turned into a counterexample to (1).

Here's one way to do it:

Let "LEM" be the universal formulation of the law of excluded middle, "∀A(A v ¬A)". And let "DNE" be the classical theorem "∀A(¬¬ A → A)". Suppose classical logic is unrestrictedly valid, so that LEM is metaphysically necessary (since logically necessary). Then the strict conditional, "□(¬ LEM → DNE)", is true. It's vacuously true. However, the corresponding counterfactual appears to be false: "¬LEM □→ DNE". This is false because if LEM were false then intuitionistic logic (and not classical logic) would be unrestrictedly valid. And in intuitionistic logic, ¬LEM does not imply DNE (but rather entails ¬DNE).

If this is right, then we also have a counterexample to (1). Although LEM is in fact metaphysically necessary, it is not equivalent to "¬LEM □→ ⊥". For in a counterfactual circumstance where ¬LEM is true, intuitionistic logic (but not classical logic) obtains. And, ¬LEM does not enjoin an intuitionistic contradiction.

Williamson evaluates other purported counterexamples to (3). I don't see that his replies touch the above example. Williamson attributes a confusion akin to the confusion made by philosophers for centuries prior to the realization that a generalization, "All S are P", is vacuously true when nothing is an S. But I'm not guilty of this confusion. If our counterfactual supposition is the denial of LEM, then not all of our knowledge of classical logical truth is available in the description of the counterfactual circumstances from which we are to develop a path to the consequent. In particular, any logical truth intuitionistically equivalent to LEM is not available in the description of the counterfactual circumstances. But then in such counterfactual (intuitionistic) circumstances, ¬LEM does not materially imply DNE. The reason is that, in those circumstances, ¬LEM is not a logical falsehood. Vacuity vanishes!

[UPDATE: Berit locates a vacuous assertion of Williamson's that he did not intend to be vacuous, and draws a dark lesson for the prospects of doing metaphysics.]

Are You Competent in Your Research Areas? (Frances)

2007-02-14T05:50:00.000+11:00

Here’s a theory about how most philosophers are working in the wrong areas. I came up with it when I was a graduate student. I don’t believe it, but I wonder how much truth there is to it.

As a graduate student one attends a bunch of classes, encounters a bunch of philosophical problems and questions, and encounters a bunch of favored responses to those problems and questions. For instance, in epistemology one hears about skepticism and the favored responses; in metaphysics one hears about the statue-clay problem and the favored responses. The students with “good sense” regarding that topic will see that none of the offered responses is very good. The students don’t have anything to offer themselves, but they see that the favored responses stink. As a result, they won’t do research in that topic, as they will find the literature a turn-off (since (a) nearly everyone in the literature is working on the favored responses, which she thinks stink, and (b) there are no known responses to work through that she thinks have a prayer of being right).

Who are the students who do end up researching the topic? Answer: the ones who got excited by it. And why did they get excited by it? Answer: in many cases, they got excited by it because they found one of the favored responses quite plausible. “Here is the solution to a philosophical issue that’s been around for centuries!” Due to this excitement, they research that topic. But they didn’t have the good sense to see that the response was lousy.

The upshot is that the people doing research on topic X are the ones who didn’t have good sense regarding X. Pretty depressing.

Clearly, this theory, competence pessimism, is overblown. For instance, one might research a topic merely because one thinks it’s a great topic, and not because one is enamored with any favored response to it. And of course one could argue that many of favored responses are really quite plausible but only appear, at first sight, to be defective. Only the people with insight into the topic can see the misleading nature of the initially apparent deficiencies of some of the favored responses. So it actually goes this way: the pessimist is right to say that the people who end up researching the topic are the ones who got excited about the topic, but the ones who got excited are the ones who correctly realized that one of the favored responses is on the right track despite its misleading appearance. That’s the opposite extreme, competence optimism, which says that the people working on topic X are the rare ones who saw that the apparent deficiencies were merely apparent. Is the truth closer to competence pessimism or competence optimism? Do you want victory for us or the terrorists?

Leon Henkin 1921-2006

2007-02-01T15:56:00.001+11:00

Leon Henkin, best known for his proof of the completeness of first order logic, died of natural causes in his home on November 1. Since the 60s Professor Henkin spearheaded various programs for the representation of women and other under-represented minorities in mathematics. He was professor emeritus in the math department at UC-Berkeley when he died. Here's an obituary.

Arizona Ontology

2007-01-23T10:21:00.000+11:00

The Arizona Ontology Conference, organized by L. A. Paul, was held at a scenic dude ranch in Tucson. I learned some ontology and how to ride a horse. Here's the program and a complete list of participants. Summaries of papers can be found at Lemmings. My pictures are here.

Update: i've added about thirty more pics.

Update: Here are more pics and a post about Jonathan Schaffer's comments, from Dave Chalmers. Yet even more pics from the conference have been posted by Brian Fiala, Andy Egan, and Benjica (Hellie and Wilson).

Sex, Singer and Ali G

2007-01-14T19:44:00.000+11:00

Peter Singer reminds us here that sex with humans is a lot more fun. And Ali G has something to say about animal rights as well.

Contradictions Rational and Justified? (Frances)

2007-01-07T00:56:00.000+11:00

Suppose Jan is taking a philosophy of logic course. She hears from several of her professors that dialetheism is the best theory for dealing with the semantic paradoxes, and most philosophers of logic even think it’s true. This is a world in which dialetheists have had some sociological success in persuading others of their odd theory.

Independently of the testimonial matter, she personally finds the case for dialetheism very convincing.

So, she has very good evidence E1 that there is good evidence E2 for her belief that proposition X (expressed by something like ‘The claim I am making with this very sentence is not true’) is both true and not true. E1 is her knowledge that most excellent philosophers of logic endorse dialetheism after plenty of expert investigation over many years. The alleged E2 is the alleged direct evidence for dialetheism—the actual philosophical arguments for it. I am not yet (see below) saying that E2 exists in this possible world or any other world. At this point I’m just saying that in this world E1 exists.

I wonder: is this a case in which one is RATIONAL in having a belief of the form ‘P and ~P’ (e.g., ‘Proposition X is both true and not true’)? She has made a mistake, we can assume, but making a mistake in the philosophy of logic is hardly grounds for irrationality.

Return to the actual world: some VERY smart people think that X is both true and not true. I find it hard to believe that all of them are irrational. Perhaps they are confused, but not irrational.

So: it appears as though one can have a rational belief of the form ‘P & ~P’. If that’s right, then it’s going to be pretty hard to formulate general principles of rationality of the form ‘It is always irrational to have beliefs of the form blah blah’.

But is Jan’s belief JUSTIFIED? Given the content of the belief, whether it is justified depends on whether she possesses good evidence for her belief. I’m inclined to think that she does have evidence sufficient for justification PROVIDED controversial philosophical views are ever justified by controversial philosophical arguments (that’s a big ‘provided’). I’m no philosopher of logic, but I take it that the argument for dialetheism is of the form, ‘Well, this is the best overall theory of the semantic paradoxes’. I also take it that many people think it’s a good argument. So now at this point I AM assuming, without any argument, that E2 exists.

Is any of this right??

Plagiarism and the President (Frances)

2007-01-04T00:31:00.000+11:00

Racecars aren’t breaking speed limits at the Indianapolis 500 Speedway. The limits don’t apply to the cars on that racetrack during that race. But what about George W. Bush?

Isn’t he a plagiarist? He “wrote” a 1254 word essay that appeared in the WSJ today. I’ll bet he didn’t write even one word of it. I suppose there are some fools who think he wrote it, but of course they are wrong. In fact, he probably had very little to do with the content of the essay. Instead, people who work for him came up with the ideas, and he okayed them. There is no way he could have come up with the ideas, let alone the words.

One could say that the usual rules of when plagiarism occurs don’t apply to the president “writing” an op-ed in a newspaper; that’s why I brought up the racecar point. But the application of plagiarism isn’t limited to academics of course. And “everybody knows he didn’t write it” doesn’t seem sufficient to avoid the charge of plagiarism, especially since not everyone knows it. The fact that the essay contains nineteen occurrences of the pronoun ‘I’ makes it worse!

So: is he obscenely guilty of plagiarism?

Modality at the APA

2007-01-02T05:00:00.000+11:00

I realize that time is an illusion and that 07 will be more of the same, but nevertheless feel compelled to drink champagne and wish you all a very happy new year.

There were some interesting talks at the APA in DC. For instance, Alan Hajek argued that most counterfactuals are false. Let P and Q be contingent formulas and suppose that it is not the case that both P and Q. Then the argument goes something like this:

1. Might and would are dual operators. That is, P []--> Q (i.e., if it were that P, then it would be that Q) is equivalent to ~(P <>--> ~Q) (i.e., it's not the case that if it were that P, then it might be that ~Q).

2. For each counterfactuals, P []--> Q, there is some objective chance that P but ~Q. So if P were the case then it might be that ~Q.

By 1 and 2, it follows that

3. P []--> Q is false.

At that session Dorothy Edgington and Bill Lycan had very interesting things to say as well. Some of the debate centered around whether the argument might go through even if premise 1 were false. Something like this would be favorable to Hajek's positions since arguably 'might' is an epistemic modal and 'would' is not. There was also disagreement about whether a natural counterfactual contextualism, analogous to epistemic contextualism, might block the argument. Hajek remained skeptical.

In an altogether different session on modality, Michael Nelson responded to Michael Fara and Timothy Williamson's paper "Counterparts and Actuality", in which it is argued that Lewis' counterpart theory (CPT) should be rejected because it is incompatible with the logic of actuality. Michael Fara was the official commentator and Williamson commented from the audience. Needless to say, Fara and Williamson were not about to let Nelson off easy. The dialectic went something like this.

Fara and Williamson argue that claims like

A: "It is possible that everyone that is actually rich was poor."

, and

B: "n is a botanist, but is not actually a botanist.",

once translated into CPT augmented with an actuality operator, deliver propositions with the wrong modal status. Contrary to what is required, the CPT translation of B is consistent (since true in models of CPT in which the denotation of 'n' has no actual world counterparts) and the CPT translation of A is false (since false in every CPT model).

Nelson offered some ways to defend CPT against this line of argument (for instance, by going second order or by adopting a 2-dimensional semantics). F and W however objected that, at least, Lewis would not be happy with these amendments since one of the advertised benefits of CPT is that it allows us to explain modality with no more than standard first-order extensional semantics.

David Sosa Gets Jiggy on Free Will

2006-12-16T17:24:00.000+11:00

Click here for impressive animation of David Sosa talking shop.

Knowledge of Metaphysical Modality

2006-12-15T17:18:00.000+11:00

Dave Chalmers points out that Timothy Williamson's book manuscript, The Philosophy of Philosophy is online. Chapter 2 is about the methodology of the vagueness debate and of analytic philosophy more generally. Chapter 5, Knowledge of Metaphysical Modality, also looks particularly interesting. Its conclusion is that the epistemology of metaphysical modality is a special case of counterfactual thinking about the spatio-temporal world.

Taking Epistemicism Seriously (Frances)

2006-12-13T13:56:00.000+11:00

If one hasn’t worked hard on the topic of vagueness, it can be hard to take epistemicism seriously. You wonder: everyone SAYS that Tim Williamson is unbelievably smart, but since he believes in cutoffs doesn’t that mean there is something seriously wrong with him? I mean, really: how much good sense could he have if he believes that my remark to a visiting speaker ‘The auditorium is a short walk from here’ is true if it’s X inches away and false if it’s X + 1 inches away? Williamson just doesn’t know when to give up on predicate calculus!

Before I thought hard about vagueness I didn’t actually have that attitude but I had some attraction to it. Now that I’ve thought hard about vagueness I think epistemicism is one of the two most plausible theories of vagueness (the other being the semantic nihilism of Sider & Braun, which says that all vague sentences aren’t true).

Shortly before Halloween you are walking to Farmer Fred’s farm. Your children want to see the pumpkins that they will carve. You say to them, in an obviously apt and relevant circumstance, ‘There is a pumpkin by the tree’. Call the situation you were in S1; so ‘There is a pumpkin by the tree’ is true when evaluated with respect to S1. Now an atom or atomic particle inside the pumpkin moves out of the pumpkin. Call the resulting situation S2. Consider the claim you made earlier, in S1, with your use of ‘There is a pumpkin by the tree’: is that claim true when evaluated with respect to S2 instead of S1? Obviously, the answer is ‘yes’, assuming there are any pumpkins and trees at all. When we consider the ordinary, everyday meaning of ‘There is a pumpkin by the tree’, given that it was true and not false in S1 it must be true when evaluated with respect to S2 as well. Continue the process and you get a series like this (pumkin claim = the claim you made in S1 when you uttered 'There is a pumpkin by the tree'), where the first column has the situations and the second column has the alethic status of the pumpkin claim:

S1 ------------ true
S2 ----------- true
S3 ----------- true
...
Sn ----------- ??
...
Sbig – 2 ---- false
Sbig – 1 ---- false
Sbig --------- false

It sure seems as though the ‘true’ entries in the second column have to stop somewhere. Perhaps the entries in the second column of our table don’t go from ‘true’ to ‘false’. That is, maybe the claim made by your use in S1 of ‘There is a pumpkin by the tree’, when applied to situations Sn – 1 and Sn goes from true to indeterminate—or maybe to indeterminately indeterminate (or indeterminately indeterminately indeterminately … indeterminate). Or maybe to just plain meaningless. Or maybe to both true and false (so it keeps being true but just adds falsity for some strange reason). Or maybe its status with respect to Sn changes with the wind, or my hair color, or some more likely factor. Or maybe it has no satisfaction status whatsoever with respect to Sn (not even meaningless). Or, what might not be any different, there might be no fact of the matter as to the satisfaction status with respect to Sn (whatever that idea comes to). Or perhaps it becomes incoherent to even apply the pumpkin claim to Sn. Or maybe it isn’t true, it isn’t false, it isn’t neither true nor false, and it isn’t neither true, false, nor neither true nor false (got that?). Finally, maybe the truth about the pumpkin claim with respect to Sn is best captured by a Zen master’s reaction to ‘What is the sound of one hand clapping?’

The great strength of epistemicism is just this: IT DOESN'T MATTER which of these many options one takes. Be as clever or as simple as you like with your theory regarding the status of the pumpkin claim, it still seems inevitable that its truth-value is ridiculously dependent on the minuscule movement of a single electron (a nanometer, say). After all, we know that the pumpkin claim applied to Sn – 1 is just plain true and not false: surely, S1, S2, S3, S4, and another trillion or so situations involved perfectly good healthy pumpkins, if pumpkins exist at all (the sum total of a trillion of these changes wouldn’t even be visible to the naked eye and wouldn’t effect the functioning of the pumpkin), and ‘There is a pumpkin by the tree’, understood to have its perfectly ordinary meaning expressed in S1, was nothing other than just plain true with respect to those trillion or so situations. However, we also know that it’s not the case that the pumpkin claim applied to Sn is just plain true (because it’s meaningless, indeterminate, indeterminately indeterminate, alethically unstable, alethically overdetermined or inconsistent, lacks any satisfaction status, [insert Zen master’s response], etc). So, something happened as a result of that ridiculously tiny change from Sn – 1 to Sn; it marks some very sharp cutoff that did not happen in the change from Sn – 2 to Sn – 1. It makes no difference (for the existence of satisfaction cutoffs) as to what descriptions of the situation after the change are correct (if any). The point is that ‘There’s a pumpkin by the tree’, understood in the perfectly normal way, is true, meaningful, and not false when evaluated with respect to the first trillion or so situations, but at some point in the series of situations it stops having that exact status.

It’s no good to protest that the table given above can’t be completed, or that it’s indeterminate whether it can be completed, or that it’s indeterminate whether it’s indeterminate whether it can be completed, or…. The first trillion or so slots in the second column CAN be completed: they all have nothing other than ‘true’ in them. Now you tell me: starting from the top, what is the last row we can correctly complete with just ‘true’? The trillionth row? Then that’s our satisfaction cutoff, and I couldn’t care less what you want to say about the trillionth row, no matter how sophisticated it is. You might want to say, ‘We might as well stop at this point, although we could have stopped earlier’. But in the trillionth row you could NOT have stopped putting in ‘true’; that would have been just as much of a mistake as if you had stopped after the first row or the thousandth row.

You might think that I’m illicitly assuming that for any pair of consecutive rows the question ‘Do they have the same alethic status?’ has an answer. Sadly, no! Most everyone will agree that ‘true’ goes in the first row, and they’ll agree that ‘Do the first and second rows have the same alethic status?’ has an answer: ‘yes, they do have the same status’. And most everyone will agree that that ‘Do the second and third rows have the same alethic status?’ has an answer: ‘yes, they do have the same status’. It doesn’t take a genius to see where this is going. If one is like Michael Tye, for instance, one will agree with what I just said about the first three rows, but one will hold that ‘Do the nth and (n + 1)st rows have the same alethic status?’ sometimes has an answer but sometimes it doesn’t. Fine: when does it first not have an answer? We know it has answer for the first three rows. Does it first fail to have an answer for rows 10,000 and 10,001? Then that’s our sharp cutoff. That is, whereas the pumpkin claim was true and not false when evaluated with respect to S10,000, there is no answer to whether it’s true and not false when evaluated with respect to S10,001.

Eventually, we take seriously both epistemicism and nihilism!

Accidental Properties and Transworld Identity

2006-12-07T16:22:00.000+11:00

The problem of temporary intrinsics, as is well known, has its modal analog---the problem of accidental intrinsics. But each of these problems cuts much deeper than their names suggest. I query whether the deeper problems have a response in the literature.

Here's the initial temporal problem. At one time Brit is bent (because sitting). Later she is straight (because standing). Is this a violation of Leibniz's Law? A well rehearsed endurantist answer is NO. We simply index to times. Brit has both the property being bent at time t and the property being straight at t+1. No contradiction here. Lewis' objection to the fix is that so called intrinsic properties (such as being straight or bent) are now treated as relational since indexed to time. In sum, there are no temporary intrinsics.

The modal analog, the problem of accidental intrinsics, arises in critique of transworld identity---the view that objects may exist in more than one possible world. In the actual world Brit is 5'10''. In other merely possible worlds she is taller. The transworlder will insist that there is no violation of Leibniz's law. Brit has both the property having height 5'10'' in the actual world and the property having height n, where n>5'10'' in world w2. No contradiction here. Again, the reply to the fix is that our intrinsic properties have suddenly become relational.

But isn't the problem with this fix to transworld identity much more general than stated? Indexing to worlds robs objects of their accidental properties (intrinsic and relational). For if an object's properties (and relations) are indexed to worlds, then the object has them necessarily. In every possible world it is true that in w1 Brit is 5'10'' (is a philosopher, lives in St Louis, etc.). The problem with indexing to worlds is then not simply a problem for accidental intrinsics, but a problem for accidental properties and relations more generally. (Analogously, the problem of temporary intrinsics underwrites a problem for temporary properties and relations more generally. No properties are temporal! A fortiori none of them are temporary intrinsics.)

Greco on Contextualism

2006-12-06T14:45:00.000+11:00

John Greco's revised draft of “What’s Wrong with Contextualism?" is now on his website. Thanks for all the lively discussion at Knowability.

Socks and Spirits Updated (Frances)

2006-12-03T12:37:00.000+11:00

The previous post on spiritual and visual experience has generated comments on several blogs. Some of the comments are based on misunderstandings of the original idea (since I did a lousy job in the initial post). Since the comments are well thought out, I thought it would be worth another post to elaborate on the socks-spirituality comparison so that the misunderstandings go away and I can be refuted properly.

In the socks case, I believe that the socks are blue, and I believe it based on my experience of them. In the spiritual case, I believe that God exists, and I believe it based on my experience of Him.

In the socks case, the scientists in question say to me ‘Yes, I agree that your experience seemed to be of blue socks. Many, perhaps most, of us had pretty much the same experience as you did from the general perspective you took. But more careful empirical examination will show that your experiences were misleading in that they were not of blue socks but really of some weird green socks. The experiences you had were genuine visual perceptions, but were somewhat crude. Further visual experience will show you your error!

In the spiritual case, the naysayers in question say to me ‘Yes, I agree that your experience seemed to be of God. Many, perhaps most, of us had pretty much the same experience as you did from the general perspective you took. But more careful empirical examination will show that your experiences were misleading in that they were not of God but instead were the beginnings of some levels of consciousness that are more advanced than those we have in most situations (and that merit the title ‘spiritual’) but don’t call out for the existence of a god. The experiences you had were genuine spiritual perceptions, but were somewhat crude. Further spiritual experience will show you your error!

In the socks case, as far as I can determine the scientists in question are about as knowledgeable about color, funny color illusions, etc. as anyone. Never mind whether there are other color experts much more knowledgeable about color.

In the spiritual case, as far as I can determine the naysayers in question are about as knowledgeable about spiritual experience as anyone. Never mind whether there are other spiritual experts much more knowledgeable about spirituality.

Finally: in the socks case the color scientists are mistaken; in the spiritual case the naysayers are mistaken. But this stipulation really isn’t very important.

That's all stipulation. Now I claim: in the socks case one is epistemically blameworthy if one retains one’s blue socks belief. Of course, one could easily avoid the blame. The main color scientist could be joking and you find out that she’s joking.

I also claim that if there’s blameworthiness in the socks story, then there’s blameworthiness in the spiritual story.

Most people have misunderstood what the theistic naysayers are saying. They aren’t saying that you (the spiritual theist) have gone insane, or that you are temporarily deranged or having a seizure or anything like that. They aren’t saying you are “screwed up”—exactly how the color scientists aren’t saying you’re screwed up. Your perceptual and spiritual faculties are working fine; it’s just that circumstances are odd and you’ve erred in interpreting them. The naysayer isn’t disrespectful, so to speak, of spiritual experience. Take the socks-spirituality analogy seriously!

In the socks case, you had some utterly typical visual experiences and immediately formed the belief that the socks are blue. We can stipulate, if you like, that the same happened in the spiritual case. I’m not saying that the move from the spiritual experience to the theistic belief amounts to any more of an “interpretation” or “inference” than in the socks case. In the spiritual case there is no more of an argument to the best explanation as in the socks case.

Defeating Perceptual and Theistic Knowledge (Frances)

2006-12-02T03:29:00.000+11:00

You see a sock in the usual excellent viewing conditions: just four feet away, in perfect light, etc. It looks, and is, blue. But it’s your colleague’s sock, and his wife is a color scientist and he insists that he is wearing some of her “trick” socks she uses in her experiments, in that although they look blue and normal, they’re actually very weird and really green. We can suppose that he’s made an innocent mistake in that the socks he is wearing are entirely normal and blue. You mistakenly think he trying to fool you even though he’s actually a pillar of honesty, so you persist in your belief that the socks are blue. Suppose his wife comes in and says ‘Well there are those trick socks! We were looking for them all morning in the lab! What are you doing with them on?’ Other people concur with her (her lab assistants and children say). She and other color theorists have created various other strange objects, strange in ways having to do with their color appearances. You are somewhat aware of these objects, involving rapidly rotating disks with special holes in them, unusual materials, and the like. So you know of the existence of such objects.

Your blue-socks belief is true and reliably produced in the entirely ordinary way, but is this belief epistemically upstanding once you’ve encountered the weird-socks story, especially given that you’ve heard and understood loads of intelligent, sincere, and honest experts saying that the socks are really green—not just his wife, but her assistants, other professors, etc.? Don’t you have to rule out, at least to some significant extent (to ask for proof seems to be asking too much) the weird-socks hypothesis to retain the upstanding status of your belief that the socks are blue? I think you would be committing some significant epistemic crimes if you retained your belief.

I just described a case that seems to have the following features: one acquires a true belief under virtually the best and most reliable circumstances possible, the belief initially amounts to knowledge, and yet the awareness of some information that is ultimately misleading but endorsed by relevant professionals and plausible given other information ruins the epistemic upstandingness of the belief (when the belief is retained after the additional information has been encountered).

I find this story interesting. First, I wonder whether it’s really the case that after encountering the ultimately misleading evidence against the blue-socks belief your blue-socks belief is epistemically blameworthy. Second, does the alleged lesson carry over to the belief that God exists? That is, assuming for the sake of argument that one can know that God exists through some kind of quasi-perceptual spiritual experiences of Him, does the presence of alternative, expertly endorsed explanations of that experience render that theistic belief blameworthy—even though the explanations are ultimately misleading?

In the theistic case I assume that one is in the position of the person in the color case: one encounters the alternative explanations and can do nothing to suggest that they’re wrong. I don’t think one can just say, “Well, the alternative explanations must be wrong, as I already know through experience that God exists”. After all, the corresponding explanation in the perceptual case doesn’t seem to work: “Well, the trick-socks explanation being offered by the color scientists must be wrong, as I already know from visual perception that the socks are blue”.

Blogger "Recent Comments" Add-On

2006-11-26T17:35:00.000+11:00

Click here for a nice "Recent Comments" add-on for your Blogger service. It's free and includes a comment feed. Just installed one on Knowability in about 15 minutes. It promises to be compatible with your eventual free upgrade to Blogger Beta.

Incidentally, my feed URLs are at the bottom of the sidebar. Consider signing in for an email subscription to posts and/or comments.

Philosophical Insults (Frances)

2006-11-22T04:34:00.000+11:00

Thanks to Joe for the invitation to communicate.

Nowadays philosophers rarely call one another idiots in print (things tend to get a little nastier in private). But this doesn’t mean that they don’t insult one another in their publications. I thought it might be fun to catalogue some of the insults from recent literature. I’d like people to share their favorites in the comments.

My favorites are the more subtle ones. Suppose Jones publishes a criticism of Smith and then Smith responds in print. Smith can insult Jones in many ways. One common way is to use the phrase ‘It is curious that’, as in ‘It is curious that Jones thinks that my view includes the claim that P’. What is often (not always) meant is this: ‘Jones is a f**king idiot. He thinks I said that P, when any fool can see that I said no such thing’. Similar points hold for ‘It is interesting that Jones thinks that I said that P’ and ‘The proposal that Jones makes on my behalf is very strange, even borderline incoherent’ and ‘I am surprised that Jones says that P’.

Here’s a rather different way to insult: ‘In a useful article’, as in ‘In a useful article, Jones considers the claim that P’. What is often (not always) meant is something like this: ‘Jones wrote a largely boneheaded article on the claim that P; however, by working through his confusions we will be able to see the important points more clearly.’ I hope it’s legitimate of me to point out that Davidson did this in one of his classic articles, although I can’t remember which one. When I was a beginning graduate student at Minnesota, and full of myself, I did it as well in a paper written for a class. My professor, Joseph Owens, drew a line through the phrase and wrote in the margin ‘Out’. It was clear that I wasn’t going to get away with such nonsense.

I don’t want to imply that these insults are never deserved. On the contrary, on many occasions the author is responding to some jerk. And even when one isn’t responding to a jerk, the insult can be non-personal in the sense that the author is such a lover of the truth and hater of the false that he or she hurls invectives not at people but merely at ideas that strike her as false. I once had a colleague who often publicly destroyed visiting speakers, but it was plain to most of us—and often enough the visiting speaker—that his target was the ideas he thought were false. It was never the person advocating the ideas. This made the behavior more tolerable, even admirable.

The insults noted above seem a bit subtle. But maybe that’s the wrong predicate. Perhaps not subtle but restrained?

Baker & Hacker insulted Kripke’s interpretation of Wittgenstein with real gusto. Hacker also insulted the recent history books by Soames, who like Kripke is a rather mediocre philosopher. But their insults are usually unrestrained. Over the years Dennett and Searle have traded many insults, or at least remarks that looked pretty insulting. But I’m not sure that all those were real insults. Dennett has a good sense of humor, and it comes out in his writing. So perhaps he wasn’t really insulting Searle, although his Journal of Philosophy review of Searle’s Rediscovery of the Mind seemed pretty tough to me. I can’t speak with any authority about Searle. Of course, in that book Seale seemed to be telling us that just about everyone in the philosophy of mind had been making terribly elementary and boneheaded mistakes for many years.

As any child will tell you, being ignored can be quite an insult. In that vein, I recall a footnote in an article on the nature of belief by some moderately famous person. He noted that perhaps he should consider what Dennett’s theory would do with the example being considered in the body of the essay. But he declined to make the probe, saying that in reality Dennett’s exceedingly vague remarks could hardly amount to anything like a view worth considering. Ouch!

So: what are your favorite examples—restrained or not? Please don’t reveal the identity of the insulter, at least if he or she is still alive and isn’t already well known as one who insults opponents. I realize that it is easy to thumb through Nietzsche, say, and find some pretty potent insults. But I’m more interested in contemporary writers, not least because I think it might be fun to try to figure out the identity of the insulter!

It also might be interesting to note which famous contemporaries never insulted any of their many critics. For instance, did Rawls or Lewis ever insult any of their critics?

David Lewis and the Future of Formal Methods

2006-11-21T09:25:00.000+11:00

SYNTHESE ANNUAL CONFERENCE

Synthese - An International Journal for Epistemology, Logic and Philosophy of Science hosts its first annual conference at the Carlsberg Academy in Copenhagen, October 3- 5 , 2007. The conference is sponsored by PHIS - The Danish Research School in Philosophy, History of Ideas and History of Science and Springer.

Title / Between Logic and Intuition: David Lewis and the Future of Formal Methods in Philosophy

Abstract / David Lewis is one of the most important figures in contemporary philosophy. His approach balances elegantly between the use of rigorous formal methods and sound philosophical intuitions. The benefit of such an approach is reflected in the substantial impact his philosophical insights have had not only in many core areas of philosophy, but also in neighboring disciplines ranging from computer science to game theory and linguistics. The interplay between logic and intuition to obtain results of both philosophical and interdisciplinary importance makes Lewis' work a prime example of formal philosophy. Lewis' work exemplifies the fruitful interplay between logic and intuition that is central to contemporary philosophy. This conference serves as a tribute to Lewis and as a venue for adressing questions concerning the relationship between logic and philosophical intuition. This first Synthese Annual Conference is the venue for discussing the future of formal methods in philosophy.

Invited Speakers / John Collins, Hannes Leitgeb, Rohit Parikh, L.A. Paul, Brian Weatherson

Program Committee and Conference Chairs / Johan van Benthem, Vincent F. Hendricks, John Symons (SYNTHESE) , Stig Andur Pedersen (PHIS)

Conference Manager / Pelle Guldborg Hansen

Call for papers / Synthese invites papers on the work of David Lewis and formal philosophy in accordance with the conference abstract. The final papers should be sent electronically to Editor-in-Chief, Vincent F. Hendricks at vincent@ruc.dk, using "SAC"-submission in the subject entry. The deadline for submitting a paper for consideration is April 1, 2007. Notification of acceptance for presentation at the conference is August 1, 2007.

Publication / A selection of the best papers will be published as an anthology in the Synthese Library book series.

Website Link

Contextualism vs. Interest-dependent Invariantism (Greco)

2006-11-02T14:18:00.000+11:00

Thanks to Joe for the invitation to post.

I want to raise some considerations about attributor contextualism and interest-dependent invariantism. (These considerations come from a paper called “What’s Wrong with Contextualism” that I am working on for Philosophical Quarterly. ) First, I want to raise some methodological considerations about how we ought to decide the case between the two. Second, I want to argue that these considerations at least point us in the direction of attributor contextualism for knowledge attributions. Here is the gist of the argument: John Hawthorne and Jason Stanley have made a lot of the idea that knowledge is the norm of practical reasoning, using this plausible thesis to argue in favor of invariantism and against contextualism. But it seems to me that the argument can be turned on its head. In other words, the idea that knowledge is for practical reasoning seems to me to count in favor of contextualism. The main idea is this: If knowledge is for practical reasoning, then it is the relevant practical reasoning context that should govern. Sometimes this is the subject-context-- we make a knowledge attribution in the context of discussion about what S should do. But other times it is the attributor context-- we make the attribution while wondering what we should do. Still other times it is a third party's context-- we are discussing what some third guy should do. Technically this turns out to be a version of attributor contextualism, since the truth value of knowledge attributions varies across attributor context. The governing idea, though, is that truth values are relative to practical reasoning contexts.

Below this idea is developed more fully.

The usual methodology for adjudicating between contextualism and interest-dependent invariantism in epistemology is two-fold: consult our intuitions about possible cases, and consult the linguistic data regarding actual language use. We may include in the latter descriptions about how certain grammatical kinds in our language in fact behave. So, for example, it is common to describe the ways that indexicals behave, and to describe analogies or disanalogies with “knows.” This methodology invites different ways to explain the relevant data. For example, contextualists and invariantists will offer competing explanations for why a knowledge claim seems true or seems false in a possible case, with one side explaining the intuition in terms of semantic competence, the other in terms of pragmatics, perhaps together with “semantic blindness.”

I think we can supplement this two-fold methodology in a fruitful way. Specifically, we can ask what our concept of knowledge and our knowledge language are for. We can ask what roles they play in our conceptual economy and our linguistic practices. By doing so, I suggest, we gain further insight about how our concepts and language can be expected to behave. This same methodology has recently been defended by Edward Craig.

There seems to be no known language in which sentences using “know” do not find a comfortable and colloquial equivalent. The implication is that it answers to some very general needs of human life and thought, and it would surely be interesting to know which and how . . . .

Instead of begining with ordinary usage, we begin with an ordinary situation. We take some prima facie plausible hypothesis about what the concept of knowledge does for us, what its role in our life might be, and then ask what a concept having that role would be like, what conditions would govern its application. (2)

What might such a “prima facie plausible hypothesis” be? Here are two ideas that have received a lot of play lately: that knowledge is the norm of practical reasoning, and that an important function of our knowledge language is to flag good information and good sources of information. The first idea is emphasized by, among others, Hawthorne and Stanley. The latter idea has been defended in detail by Craig.

Human beings need true beliefs about their environment, beliefs that can serve to guide their actions to a successful outcome. That being so, they need sources of information that will lead them to believe truths . . . So any community may be presumed to have an interest in evaluating sources of information; and in connection with that interest certain concepts will be in use. The hypothesis I wish to try out is that the concept of knowledge is one of them. To put it briefly and roughly, the concept of knowledge is used to flag approved sources of information. (11)

Putting the two ideas together, we get the following plausible thesis: that an important function of our concept of knowledge and our knowledge language, perhaps its primary function, is to flag information and sources of information for use in practical reasoning.

Now suppose this is right. Does that speak in favor of attributor contextualism or interest-dependent invariantism? To my mind, it speaks in favor of attributor contextualism. More specifically, it speaks in favor of the version of attributor contextualism that allows the attributor context to be sensitive to the interests and purposes operative in the subject context. My thinking is this: if the function of knowledge is to serve practical reasoning, it should be tied to the interests and purposes that are relevant to the practical reasoner.

To make the point more clearly we may use Hawthorne’s notion of a “practical environment.” One’s practical environment is constituted by those aspects of one’s environment that are relevant to practical reasoning. Often enough, the practical reasoner with whom we are concerned will be in the attributor’s practical environment. Often enough, that is, one attributes knowledge for the purpose of practical reasoning in one’s own practical environment. But sometimes the practical reasoner will be outside the attributor’s practical environment. For example, sometimes we attribute knowledge for the purpose of practical reasoning in the subject’s practical environment. In that case, it would seem, it is the interests and purposes operative in the subject’s practical environment that are relevant.

These considerations suggest the following general rule: the truth-value of knowledge attributions (and the like) depends on the interests and purposes operative in the relevant practical reasoning context. Sometimes this will be the practical environment of attributor, sometimes that of the subject, and sometimes that of some third party. The position that results, however, will be a version of attributor contextualism, since it entails that the truth-value of knowledge claims is variable over attributor contexts. More exactly, the position is a version of interest-dependent, subject-sensitive contextualism.

As I said above, these remarks are at best suggestive. I don’t pretend to have established the present version of contextualism over its competitors. It is worth noting, however, that the proposed view does very well in relation to Hawthorne’s scorecard for evaluating contextualist and invariantist positions. In fact, it does better than any position that Hawthorne considers. Not pretending to have argued for these claims, I will simply assert the following: subject-sensitive contextualism respects the Moorean constraint that most of our knowledge claims are true, respects plausible closure principles, preserves the intuitive connections between knowledge, assertion and practical reasoning, and can (near enough) respect disquotational schemas for ‘knows’. We get this last result because all knowledge attributions must satisfy fairly high minimal standards, and so a knowledge claim in one context can normally be imported into another. I say “near enough” because there will be exceptions to this general rule. Specifically, we cannot disquote into contexts where stakes drive relevant standards unusually high. That there are such exceptions, however, seems correct. That is, we do not expect disquotation to go in that direction. (Hawthoren correctly notes that no anti-skeptical view can respect both the “Epistemic Possibility Constraint” (If the probability for S that p is not zero, then S does not know that not-p) and the “Objective Chance Principle” ( that epistemic probability follows knowledge of objective probability). (94))

Finally, the proposed view deals nicely with a kind of counter-example that gets posed against contextualism--ones involving attributions of knowledge to a high-stakes subject context from a low-stakes attributor context. For example, consider the case where we are considering whether S “knows” that the bank is open on Saturday, based on the evidence that he was at the bank two weeks ago and it was open on Saturday then. Nothing much depends on his being right for us but a lot depends on it for him. Intuitively, we should judge that S’s claim to “know” is false, even though we are evaluating his claim from a low-stakes context. As Hawthorne and Stanley point out, it seems that it is the interests and purposes operative in the subject’s practical environment that should govern the standards for “knowledge” here. But so long as the attributor context can be properly sensitive to the interests operative in the subject’s practical environment, attributor contextualism can accommodate this point. More specifically, insofar as it is the practical reasoning of the subject that is at issue in the case, the present view rules that it is the interests and purposes operative in the subject’s practical environment that ought to govern our evaluation of the knowledge claim. On the other hand, if the knowledge claim is being evaluated for use in our own practical reasoning, then it is the interest and purposes operative in our own practical environment that should govern. All that seems intuitively correct to me. That is, the proposed position seems to me to yield the right results in each case.

Is Knowledge Composite or Prime?

2006-10-22T16:27:00.000+10:00

In Chapter 3 of Knowledge and Its Limits, Timothy Williamson offers recombination arguments for the primeness of knowledge (and other mental states). To say that knowledge is prime is to deny that it is a composite of narrow (internal) and broad (external) conditions. Each argument begins with two cases of knowledge that are like with respect to their internal condition but different with respect to their external condition. If knowledge is composite, then recombining the internal condition of one case with the external condition of the other case will produce a third case of knowledge. Williamson needs one such recombination that fails to produce a case of knowledge to undermine the thesis that knowledge is composite. Here's Williamson:

...in [case 1] there is water on the right and gin (which looks just like water) on the left, and a brain lesion causes one visually to register only what is on the right. In [case 2] there is gin on the right and water on the left, and a brain lesion causes one visually to register only what is on the left; in the [case 3] internally like [case 1] and externally like [case 2], there is gin on the right and water on the left (as in [2]), and the brain lesion causes one visually to register only what is on the right (as in [1]). Thus, given appropriate background conditions one sees water in [1] and [2] but not in [3]. (70)

My criticism of Williamson's argument is this. It is all but clear that cases 1 and 2 are in fact cases of seeing. After all, for Williamson seeing entails knowing (Chapter 1), and he is sympathetic to the thesis that one can know only if she could not easily have gotten it wrong (Chapter 4). But it would seem that in cases 1 and 2 the subject could very easily have gotten it wrong, since she could very easily have looked at the gin when forming her water-belief. The worries here are the same for barn-beliefs in Barn County. Just as it seems strange to say that I know that there is a barn when there are fake barns in the vicinity, it seems strange to say that the subject in cases 1 and 2 knows that there is water when there is gin (indistinguishable from water) in the vicinity. Additionally, the subject in each of the two cases has a brain lesion blocking half of her visual information! One would not be remiss to pause and question the respectability of the partially disabled visual process. In sum, two worries arise. There are Ginet-Goldman style barn considerations to worry about, and there are Bon Jour-Plantinga clairvoyance-brain lesion considerations about the epistemic respectability of strange but reliable belief-forming processes. Both worries go against a claim to knowledge in cases 1 and 2. And so, if seeing entails knowing, then arguably the subjects in cases 1 and 2 fail to see. Related worries surround Williamson's other arguments. Here is Williamson arguing more directly for the primeness of knowledge.

Let [case 1] be a case in which one knows by testimony that the election was rigged; Smith tells one that the election was rigged, he is trustworthy, and one trusts him; Brown also tells one that the election was rigged, but he is not trustworthy, and one does not trust him. Let [2] be a case which differs from [1] by reversing the roles of Smith and Brown.... Now consider a case [3] internally like [1] and externally like [2]. In [1], one does not trust Brown, because one does not trust him in [1], and [3] is internally like [1]. Equally in [3], Smith is not trustworthy, because he is not trustworthy in [2], and [3] is externally like [2]. Thus, in [3], neither Smith nor Brown is both trustworthy and trusted. Consequently, in [3], one does not know that the election was rigged. Thus the condition that one knows that the election was rigged is prime. (72)

My criticism here is this. In recombining the internal condition from case 1 and the external condition from case 2, Williamson fails to include the entire external condition from case 2. Part of the external story in case 2 is that the belief in question was produced by reliable testimony. In case 3, the belief was not produced by reliable testimony. But if in case 3 the belief was not produced by reliable testimony, then Williamson has not properly recombined the cases. He has not included in case 3 the full external condition from case 2. Therefore, the recombination is incomplete.

A general criticism that I am making is that Williamson, in all of his recombination arguments, fails to include some causal or counterfactual conditions as part of the broad (external) condition of the subject in cases 1 and 2. The result is a mistaken attribution of knowledge in the first argument and an incomplete recombination in the second argument. Therefore, the question about the primeness of knowledge remains open.

The Most General Factive Mental State Operator

2006-10-04T06:51:00.000+10:00

Last week I re-read the first chapter of Timothy Williamson's Knowledge and Its Limits. TW argues that 'knows' is the most general factive mental state operator. To be a factive mental state operator (FMSO) is to be a factive semantically unanalyzable expression that attributes a propositional attitude to a subject. The semantic unanalyzability claim is that, by definition, an FMSO is never synonymous with a complex expression whose meaning is composed of the meanings of its parts. So, for instance, 'could hear' is a FMSO. There is a reading of it such that the presumption of truth is not cancelable, as is revealed by the deviance of

(1) She could hear that the volcano was erupting, but it was not erupting.

Moreover, the meaning of 'could hear' is not composed of the meanings of 'could' and 'hear', for that would assimilate 'could hear' to something like 'it is merely possible that s heard that p', which is not factive.

Additionally, 'could hear' is further evidence that 'knows' is the most general FMSO, since 's could hear that p' implies 's knows that p'.

Let's explore the properties of other FMSOs. I want to argue that there is a more general FMSO than 'knows'.

Consider the ambiguity in each of the following expressions:

'could see that'

'could hear that'

'could feel that',

'can't believe that'

'is not happy that'

'is not surprised that'

'failed to realize that'

'is not impressed that'

'is not able to taste that'

Each of these has a factive and a non-factive reading. For instance, 'cannot believe' is factive in

(2) I cannot believe that you are smoking again,

but is not factive in

(3) I cannot believe that I don't have any beliefs.

Now the non-factive readings of the above list items are semantically decomposable. They may be paraphrased roughly as

'it is false that s believes/is happy/is surprised/realizes/is impressed/is able to taste that'

or

'it is (merely) possible that the subject s sees/hears/feels that'.

Exactly analogous remarks may be made about knowability- and ignorance-attributions. More carefully, 'could have known that' and 'does not know that' both have a factive and a non-factive reading. Let's discuss 'could have known that'. The non-factive reading, perhaps not common in ordinary English, is that it is merely possible that s knows that p. The other reading carries a presumption of truth as in 's was in a position to know that p'. Notice that the presumption of truth is not cancelable. This is demonstrated by the deviance of the following claims:

(4) Andy could have known that grandmother was ill, even though she was not ill.

and

(5) Sally was in a position to know that Andy was cheating, but he was not cheating.

The deviance of the claims suggests that the presumption of truth is semantic and not cancelable.

As with the factive readings of the items on the above list, we should expect that the factive readings of 'could have known that' and 'is not known that' are not analyzable. My hypothesis is that they are not analyzable. And I suggest that the burden is on one who thinks otherwise to show that 'could have known' is different from all of our other factive operators of the form 'could have ___ed'.

Incidentally, the non-factive readings of all of the aforementioned expressions fail to attribute a propositional attitude to a subject. They either outright deny the presence of the attitude or affirm merely its possibility of obtaining. The factive readings of the above operators, on the other hand, all attribute a propositional attitude to a subject (with the exception of 'does not know that').

According to Williamson, when a propositional attitude that p is attributed, so is a grasp of the concepts in p. Since the factive reading of 'does not know' fails to attribute grasp of meaning, we may conclude that it is not a mental state operator. A fortiori it is not an FMSO. Importantly, 'could have known' does attribute grasp of meaning. Consider,

(6) Andy doesn't understand high-energy physics, yet he could have known that there are top quarks in pp collisions.

Or

(7) Andy doesn't grasp any of the rules of Chess. He was nevertheless in a position to know that his King was about to be mated.

The oddities of (6) and (7) suggest that knowability is a mental state---that 'to s it is knowable that p' implies 's has an attitude that p'---minimally, it implies 's grasps the meaning that p'. Similar things can be said about 's failed to realize that p'. It wouldn't be a failure to realize that p, if the subject didn't have a grasp of the concepts in p.

It would seem then that 'knowable' or 'could have known' is an FMSO. The problem for Williamson's account is that 's could have known that p' does not entail 's knows that p'. Hence, 'knows' is not the most general FMSO. Instead, the entailment goes the other way. Are we to conclude that 'could have known' is the most general FMSO?

Löb's Legacy

2006-09-21T07:55:00.000+10:00

Richard Zach's Log Blog has brought to my attention the recent death of Martin Löb. It is fitting that we think here about his work. The famous Löb Theorem (in "Solution of a Problem of Leon Henkin" JSL, 1955) generates Löb's paradox (ibid.), which goes something like this:

(*) If this sentence is true, then so is A.
Notice that (*) is provable for an arbitrary proposition A. Here's the proof. Suppose (*) is true. Then it satisfies its own antecedent. So it follows that A. By conditional proof, if (*) is true then so is A. And that is just to say that (*) is true.

Notice also, that the provability of (*) underwrites the truth of any proposition A. For this reason and since both (*) and its proof are negation-free, Löb offers (*) as a test for inconsistency of negation-free languages (that allow self-reference).

Löb credits an anonymous referee for extracting the paradox and the insight about how to test for inconsistency without negation. Curry (1942), and not Löb (1955), usually gets credit for the above insights. Johan van Benthem ("FourParadoxes" JPL 1978), however, argues that the Löb+Referee insights were developed independently of Curry's work. Moreover, the Curry paradox is treated by Curry and his students as a feature of formal systems only, whereas Löb's paradox is a natural language paradox.

An interesting loose-end is the identity of the 1955 anonymous referee that extracted the paradox from Löb's Theorem.

Call for Papers: Knowability and Beyond

2006-09-18T14:23:00.000+10:00

CALL FOR PAPERS (May 1, 2007)

Knowability & Beyond
Special issue of Synthese

Can there be non-actual knowledge of what is actually the case?
Is the concept of knowability basic or is it semantically decomposable into knowledge and (alethic) possibility?
Should an intuitionist find a way to express an existential commitment to some ignorance and undecidedness?
Are there more truths than knowables?

These are possible topics for a special issue of Synthese that I will be editing. For a description of the issue and further details please go here.

Visitors at Knowability

2006-09-11T08:25:00.000+10:00

Sporadically one will find here at Knowability a post authored by someone not identical to me. The explanation is that, although this is not currently a guest blog, I will be hosting visitors now and again. I look forward to these visits.

The Logical Necessity of Some Ignorance

2006-09-06T05:12:00.000+10:00

Modest modal epistemic reasoning reveals the equivalence of the following two principles:

(1) Any truth can be known.

(2) All truths are known.

Jon Kvanvig, in his latest book The Knowability Paradox (2006), poses a challenge to anyone who accepts the validity of the reasoning---viz., explain the loss of the apparent logical distinction between these two principles. Here's one way to go.

It is logically necessary that each of the above propositions is false. Logically necessary propositions often appear to express different thoughts, especially if one involves a concept not involved in the other.

Why think that the above propositions are necessarily false? An appendix to Nicholas Rescher's Epistemic Logic (2005) inspires an answer. It is a logical fact that there are more truths than knowables. Knowledge requires thought, and we could at most think a countable number of propositions. However, the true propositions themselves are uncountable. A diagonalization argument is required to make this stick, but it shouldn't be difficult to construct one for, say, a class of truths about the rational numbers. So if (i) there are more truths about the rational numbers than things that can be known about the rational numbers and (ii) the proof of this rests on no non-logical facts, then it is logically necessary that there is an unknown truth. (2) is logically false. And by the same reasoning so is (1).

The apparent logical distinction is explained by the fact that (2) seems on first glance to be stronger than (1). But the appearance is the result of not immediately recognizing that both propositions are logical falsehoods.

Action Shots from Stirling

2006-08-30T04:35:00.000+10:00

Shots from the Stirling epistemic value conference can be found here.

A couple photos from the Danish epistemology workshop are here.

Fantle and McGrath Against Epistemic Purism

2006-08-26T06:03:00.000+10:00

Fantle and McGrath have an excellent new paper on pragmatic encroachment.

The latest version of the Fantle and McGrath argument against epistemic purism goes like this. Suppose that possible subjects S1 and S2 are alike with respect to strength of epistemic position. For instance, we suppose that they share precisely the same evidence regarding a true proposition that p. And we suppose that S1 knows that p. S2 is just like S1 in every respect accept that she differs with respect to stakes. The matter is much more important to S2, and so she is not rational to act as if p. But then by the pragmatic condition on knowledge, S2 fails to know p. And since, ex hypothesi, S1 does know p, it therefore follows that whether one is in a position to know does not supervene on strength of epistemic position. Epistemic purism is false.

The argument harbors some fundamental assumptions. First, subjects S1 and S2 are thought to be the same with respect to position of epistemic strength because they are said to be evidential twins. One implicit fundamental assumption then is this: only evidence effects position of epistemic strength. Second, S1 and S2 are thought to be evidential twins, because it is thought that practical interests do not effect how much evidence one has.

The notion of evidence, for F and M, is meant to be "a broad intuitive concept, that internalists and externalists might analyze in different ways." And in defense of their position, they remark that "it ought to be common ground between theories of evidence that having a lot at stake in whether p is true does not, by itself, provide evidence for or against p." Further, they explain that evidence for p, but not stakes in whether p, affect the probability of p (in some appropriate sense of 'probability').

Here is a possible reply that I discussed at the Epistemic Value Conference. Having a lot at stake does affect evidence. Consider, when stakes are high, evidence previously ignored becomes salient. Such "new" evidence may reduce the probability that p is true. For instance, S1 knows that the train is the Express train based on another traveler's testimony, but had it meant more to him to be right he might have recalled that a small number of travelers are clueless. Weighing in that a small number of travelers are clueless suddenly reduces the probability that the train is the Express. If practical interests can make salient previously ignored evidence, then Assumption 2 is false. Practical interests do affect the amount of evidence one has, and so, by Assumption 1, practical interests (at least indirectly) affect the strength of one's epistemic position.

Danish Epistemology Workshop

2006-08-25T01:52:00.000+10:00

The Danish Epistemology Network, Namicona, and the Department of Philosophy at the University of Copenhagen hosted an epistemology workshop on August 22. Speakers included Lars Gundersen (Aarhus), Jesper Kallestrup (Edinburgh), Berit Brogaard and yours truly.

Gundersen developed an account of why neither disjunctivism nor contextualism has the resources for dealing adequately with “abominable conjunctions”. The natural way for these theories to deal with such conjunctions leaves them vulnerable when we reformulate the conjunctions in terms of claimability/assertibility: (1) it is claimable that I know that p (where p is some ordinary proposition); (2) if it’s claimable that p and claimable that p entails q, then it is claimable that q; and (3) it is not claimable that I know that q (where q is the negation of the skeptical hypothesis).

Kallestrup’s paper, “Reliabilist Justification: Basic, Easy and Brute”, offered a way of blocking track-record versions of the easy knowledge objection. The key is to motivate a Wrightian restriction on the transmission of justification across valid deduction. Doing so blocks the very first inferential step in the track-record/bootstrapping arguments.

Brogaard in her presentation “In Defense of a Perspectival Semantics for ‘Knows’” first defends relativism against objections (including Stanley’s objections that it cannot accommodate the factivity of ‘knows’ and that it entails that circumstances of evaluation have features that cannot be shifted by any intensional operator), but then shows that a perspectivalist semantics can do all the same work without relativizing sentence truth to contexts of assessment.

I presented “Knowability Noir: 1945-1963”, which evaluates an unpublished debate between Fitch and Church in 1945. Their debate was primarily over the effectiveness of the proof we today call the “knowability paradox”. My primary concern was to offer an account of what Fitch perceived to be the significance of the proof in his 1963 paper. I argued that the significance was to draw general and special lessons about how to avoid conditional fallacies in philosophical analysis.

Epistemic Value (Day 2)

2006-08-25T01:40:00.000+10:00

The final day of the epistemic value conference included a paper by Ward Jones. He developed some ideas about the nature of doxastic goods in his attempt to say what it is that makes knowledge valuable. Pascal Engel’s position was that none of the arguments for pragmatic encroachment on truth, evidence, justification or knowledge work. Christian Piller argued that our interest in truth is not captured by the idea that we desire to believe all and only truths. In particular, he argued, that we do not wish to believe only truths. And Martin Kusch developed an account of the social value of knowledge partially in terms of a very interesting fictional geneology of a proto-concept of knowledge.

Epistemic Value Conference (Day 1)

2006-08-20T11:09:00.000+10:00

Here are some highlights from a full day of interesting talks at the epistemic value conference. Wayne Riggs developed a conception of epistemic luck to compliment his credit approach to the value problem. Much use was made of Jennifer Lackey's published criticisms of the credit approach and her criticisms of Pritchard's theory of luck.

Matt Weiner explained that knowledge is like a Swiss army knife. Its value is derivative of the value of its components. Moreover, knowledge is not more valuable that any of its proper parts. Matt's positions hinged on the connections between knowledge and practical rationality.

Berit Brogaard argued that a perspectivalist semantics supports epistemic value monism better than does contextualism or relativism. Along the way she denies that there are any genuinely relative truths.

Mark Kaplan came to terms with human fallibility by arguing that a determination of one's confidence that p does not determine her opinion regarding p; "being confident" is different from "being willing to say". Without paradox I can take it to be highly likely, say, that there are errors in my book, even though I endorse all of the claims therein.

There were other interesting talks as well. Must get some sleep before tomorrow's marathon.

Epistemic Value Conference (Day 0)

2006-08-19T14:59:00.000+10:00

Today was the pre-conference workshop on epistemic value at the University of Stirling. Stephen Grimm set up a dilemma for epistemic value monism. Either epistemic appraisals apply only to "interesting truths" (Alston, Goldman) or they apply to all truths equally (Lynch). If the former, then absurdly epistemic appraisals such as 'is justified' do not apply to uninteresting true beliefs. If the latter, then believing that there are n blades of grass in the yard is absurdly as valuable as any other belief.

Jason Baehr argued that the guiding intuition behind the value problem does not warrant the standard formality and generality constraints on a solution. That is, the intuition that knowledge is more valuable than mere true belief does not motivate the traditional thought that one or more components of knowledge must have "truth-independent" value or the thought that knowledge is always more valuable than true belief.

Jay Wood discussed a wide spectrum of epistemic values and argued against a sharp distinction between epistemic and moral value.

Epistemic Value Conference

2006-08-14T02:24:00.000+10:00

This week I'm off to the conference on Epistemic Value at the University of Stirling. If my laptop isn't confiscated at the airport and I have internet access, then I expect to report from there.

Church's Solution to the Knowability Paradox

2006-07-30T06:40:00.000+10:00

In Church's "First Anonymous Referee Report on Fitch's 'A Definition of Value'" from 1945 we find not only the first formulation of the proof today known as the knowability paradox, but we find the first proposed solution. Church rejects any principle stating that propositional attitudes necessitate (other) propositional attitudes. For instance, Church rejects plausible closure principles for belief. He explains,

To be sure, one who believes a proposition without believing its more obvious logical consequences is a fool; but it is an empirical fact that there are fools. It is even possible there might be so great a fool as to believe the conjunction of two propositions without believing either of the two propositions; at least, an empirical law to the contrary would seem to be open to doubt. On this ground it is empirically possible that a might believe k' at time t without believing k at time t (although k' is a conjunction one of whose terms is k.

Church here denies that belief is closed under conjunction elimination. The context reveals that he is also denying that knowledge is so closed. More generally the idea is that if a propositional attitude is the result of another, it is so contingently. Notice that we have today departed dramatically from Church's thought. In all of the literature on the knowability paradox, for instance, it is granted that it is at least metaphysically necessary that one knows the conjuncts of known conjunctions. An exeception is found in a position articulated in Kelp and Pritchard's very interesting forthcoming " Anti-realism, Factivity and Fitch".

To pick another example,

...there is no valid law of psychology according to which anything whatsoever about my desires may be inferred from the fact that I know so-and-so.

It should be noted that Church (in the second referee report) allows Russell's theory of types to avoid such obvious counterexamples as "Necessarily, if a knows that she desires that p then a desires that p". Accordingly, the approach blocks the instance of the factivity of knowledge that is employed in the knowability paradox---viz., K(p & ~Kp) => (p & ~Kp). In this regard Church forshadow's Bernie Linsky's independent thoughts on the matter, forthcoming as "Logical Types in Arguments about Knowability and Belief".

In sum, Church's position is that his knowability paradox is indeed an invalid proof. On his view knowledge is neither closed under conjunction elimination nor unrestrictedly factive.

Fitch, Church and Nagel Papers

2006-07-28T15:34:00.000+10:00

The following is a chronological catalog of archival documentation pertaining to the early history of Fitch's knowability paradox. The items were identified for the first time by myself or those aiding my research. I discuss their content in "Knowability Noir: 1945-1963", which will appear in New Essays on the Knowability Paradox.

The documents can be found in one of three archives:

(FFP) Frederic B. Fitch Papers: Manuscripts and Archives. Yale University Library.

(ACP) Alonzo Church Papers: Department of Rare Books and Special Collections. Princeton University Library.

(ENP) Ernest Nagel Papers: Rare Book and Manuscript Library. Columbia University.

*****************************************

* Church, Alonzo. "First Anonymous Referee Report on Fitch's 'A Definition of Value'". January or February 1945. Hand written by Alonzo Church to Ernest Nagel, coeditor of JSL. Contains the first proof of the modal epistemic result, today known as the knowability paradox. (ENP: Box 1)

An edition of this and the second referee report (listed below) is being prepared by Julien Murzi and myself for publication in New Essays on the Knowability Paradox.

* Nagel, E. "Letter to Church: March 6, 1945". Explains that Fitch has returned the manuscipt and offered replies to the first report. (ACP: Box 20)

* "Second Anonymous Referee Report on Fitch's 'A Definition of Value'". Late March or early April 1945. Includes a more formal characterization of the knowability result in Lewis and Langford's proof theory. Includes replies to Fitch's discussion of the first report. (ENP: Box 1)

* Nagel, E. "Letter to Church: April 13, 1945". Announces that Fitch has withdrawn his paper owing to a defect in his definition of value. (ACP: Box **)

* Fitch, F. "A Logical Analysis of Some Value Concepts". Fitch's December 23, 1961 Presidential Address to the Association for Symbolic Logic. (FFP: Box 33)

* Fitch, F. "A Logical Analysis of Some Value Concepts". Penultimate draft. (FFP: Box 33)

* Postcard to Fitch: January 18, 1963. Regarding remaining typographical edits to be made prior to the printing of "A Logical Analysis of Some Value Concepts" in JSL. (FFP: Box 33)

Introduction to New Essays

2006-07-19T03:46:00.000+10:00

I've attached here a pdf of a draft of the introduction to New Essays on the Knowability Paradox. Comments Sought.