If you want to nominate an article from the last two years for the “APA Article Prize”:http://www.apa.udel.edu/apa/opportunities/prizes/article.html, note that the deadline for nominations is March 15. The last two article prizes have been won by friends of mine, as was the last book prize, so I’m hoping for a continuation of this trend. Articles with a publication date of 2004 or 2005 written by folks under 40 at the time of publishing are eligible for the prize, which is worth $2000. More information, including info on how to nominate, is “here”:http://www.apa.udel.edu/apa/opportunities/prizes/article.html.

“Jason Stanley reports”:http://leiterreports.typepad.com/blog/2006/02/in_memoriam_sir.html the sad news that Sir Peter Strawson has died. I’ll try and keep this post updated with links to the obituaries.

* “Times of London”:http://www.timesonline.co.uk/article/0,,60-2040505_1,00.html
* “Daily Telegraph”:http://www.telegraph.co.uk/news/main.jhtml?xml=/news/2006/02/15/db1501.xml&sSheet=/portal/2006/02/15/ixportal.html
* “Guardian”:http://www.guardian.co.uk/obituaries/story/0,,1709718,00.html

UPDATE: Jason Stanley has more “thoughts on Strawson here”:http://leiterreports.typepad.com/blog/2006/02/some_personal_r.html.

Here are some of Sir Peter Strawson’s books:

* The Bounds of Sense
* Entity and Identity: And Other Essays
* Analysis and Metaphysics

Jim Pryor sent a link to the following “amusing correction”:http://www.nytimes.com/2006/02/12/magazine/12cxn.html?_r=1&ex=1297400400&en=dd4c&oref=slogin.

bq. An interview on June 5, 2005, with Carl Icahn misstated a word of the title of a thesis he wrote while he was an undergraduate at Princeton. As a reader informed The Times two weeks ago, it is “The Problem of Formulating an Adequate Explication of the Empiricist Criterion of Meaning,” not “Imperious Criterion.”

I’m a rationalist, so I think writing ‘imperious’ for ’empiricist’ isn’t that bad, but still, this shouldn’t happen!

On the weekend I put up a post on “updating vague probabilities”:http://tar.weatherson.org/archives/004680.html which was meant to come after, not before, “this frivolous post on conditionals”:http://tar.weatherson.org/archives/004683.html. Sadly my blogging skills prevented this. Anyway, “Seth Yalcin”:http://mit.edu/yalcin/www/ pointed out that he had a similar idea that he puts to very good use towards the end of his “theory of epistemic modals”:http://mit.edu/yalcin/www/epmodal-dec05.pdf. So credit to Seth for this idea, and go check out “his paper”:http://mit.edu/yalcin/www/epmodal-dec05.pdf.

Over at Certain Doubts, they’re having “a discussion of Sly Pete conditionals”:http://bengal-ng.missouri.edu/~kvanvigj/certain_doubts/?p=514. Jon Kvanvig says, a propos of the pair of conditionals uttered,

bq. Both assertions are appropriate, but both can’t be true (without introducing contextuality into the account).

I think that’s not right unless you’re just going to ignore the relativist. (Or treat the relativist as a kind of contextualist.) I think that both assertions are appropriate because both are true relative to the context in which they are uttered, though only the second assertion is true in both contexts. Some days I think that the Sly Pete cases are the strongest cases for relativism about indicative conditionals, which seems to be a very plausible theory to me.

In fact, it’s one of the four (major) things I want to do this year. I’m writing out that list here as a way of reminding myself to do them, and perhaps providing some needed encouragement. (Unlike “Jason”:http://leiterreports.typepad.com/blog/2006/02/philosophy_of_l.html if I’d only written a 60 page article by February 10 I wouldn’t appear to regard that as having not done much!) Here they are:

* Finish up the paper on “conditionals and relativism”:http://brian.weatherson.org/car.pdf
* Write a paper on epistemic agency (defending my crazy beliefs about doxastic voluntarism and making them do epistemological work)
* Extend the paper on “epistemic justification for functionalists”:http://brian.weatherson.org/cwdwpe.pdf to a paper on knowledge for functionalists
* Write a paper on the state of play in debates about dogmatism

There should be more on the last point later this weekend, embedded in a long post I’m working on concerning heterodox approaches to probabilistic updating. If that doesn’t excite you about what’s upcoming, I don’t know what will!

“Arché”:http://www.st-andrews.ac.uk/~arche now has “a blog”:http://www.archeans.blogspot.com/ where all members of Arché can post. (I’m not exactly sure who is a member in this context. I don’t think I’m one, though I have some connection to the vagueness project.) So far it’s just Robbie Williams and Roy Cook posting, but I’m sure there will be more to come.

bq. “Arché blog”:http://www.archeans.blogspot.com/

HT: “Carrie Jenkins”:http://longwordsbotherme.blogspot.com/2006/02/new-arche-blog.html

I’ve been thinking a bit recently about the following position, and I couldn’t see any obvious reason why it was _incoherent_, so I was wondering whether (a) it might be true or (b) I was missing something obvious about why it was incoherent. So feedback on it is more than welcomed.

Many Bayesians model rational agents using the following two principles

* At any moment, the agent’s credal states are represented by a probability function.
* From moment to moment, the agent’s credal states are updated by conditionalisation on the evidence received.

Of course these are idealisations, and many other people have been interested in relaxing them. One relaxation that has got a lot of attention in recent years is the idea that we should represent agents not by single probability functions, but by _sets_ of probability functions. We then say that the agent regards q as more probable than r iff for all probability functions Pr in the set, Pr(q) > Pr(r). This allows that the agent need not hold that q is more probable than r, or r more probable than q, or that q and r are equally probable, for arbitrary q and r. And that’s good because it isn’t a rationality requirement that agents make pairwise probability judgments about all pairs of propositions.

Now what effect on the model does this relaxation have on the principle about updating? The standard story (one that I’ve appealed to in the past) is that the ideal agent updates by conditionalising all the functions in the set. So if we write Pr_E for the function such that Pr_E(x) = Pr(x | E), and S is the set of probability functions representing the agent’s credal state before the update, then {Pr_E: Pr is in S} is the set we get after updating.

Here’s the option I now think should be taken seriously. Sometimes getting evidence E is a reason for the agent to have more determinate probabilistic opinions than she previously had. (I’m using ‘determinate’ in a sense such that the agent represented by a single probability function has maximally determinate probabilistic opinions, and the agent represented by the set of all probability functions has maximally indeterminate opinions.) In particular, it can be a reason for ‘culling’ the set down a little, as well as conditionalising on what remains. So we imagine that updating on E involves a two-step process.

* Replace S with U(S, E)
* Update U(S, E) to {Pr_E: Pr is in U(S, E)}

In this story, U is a function that takes two inputs: a set of probability functions and a piece of evidence, and returns a set of probability functions that is a subset of the original set. (The last constraint might want to be weakened for some purposes.) Intuitively, it tells the agent that she needn’t have worried that certain probability functions were the ones she should be using. We can put forward formal proposals for U, such as the following

bq. Pr is in U(S, E) iff Pr is in S and there is no Pr* in S such that Pr*(E) > 2Pr(E)

That’s just an illustration, but it’s one kind of thing I have in mind. (I’m particularly interested in theories where U is only knowable a posteriori, so it isn’t specifiable by such an abstract rule that isn’t particularly responsive to empirical evidence. So don’t take that example too seriously.) The question is, what could we say against the coherence of such an updating policy?

One thing we certainly can’t say is that it is vulnerable to a Dutch Book. As long as U(S, E) is always a subset of S, it is easy to prove that there is no sequence of bets such that the agent regards each bet as strictly positive when it is offered and such that the sequence ends in sure loss. In fact, as long as U(S, E) overlaps S, this is easy to show. Perhaps there is some way in which such an agent turns down a sure gain, though I can’t myself see such an argument.

In any case, the original Dutch Book argument for conditionalisation always seemed fairly weak to me. As Ramsey pointed out, the point of the Dutch Book argument was to dramatise an underlying inconsistency in credal states, and there’s nothing inconsistent about adopting any old updating rule you like. (At the Dutch Book symposium last August this point was well made by Colin Howson.) So the threshold for endorsing a new updating rule might be fairly low.

It might be that the particular version of U proposed above is non-commutative. Even if that’s true, I’m not 100% sure it’s a problem, and in any case I’m sure there are other versions of U that are commutative.

In the absence of better arguments, I’m inclined to think that this updating proposal is perfectly defensible. Below the fold I’ll say a little about why this is philosophically interesting because of its connection to externalist epistemologies and to dogmatism.
Continue reading →

“David Chalmers”:http://consc.net/chalmers/, who it seems now has a “wikipedia page”:http://en.wikipedia.org/wiki/David_Chalmers has posted a new paper.

bq. “Scott Soames’ Two-Dimensionalism”:http://consc.net/papers/soames2d.pdf

(Should that be Soames’ or Soames’s?) As the title suggests, Dave thinks Soames has drifted towards _endorsing_ a kind of two-dimensionalism. The paper is for an author meets critics session at the APA Central that will also feature Robert Stalnaker.

The “BBC reports”:http://news.bbc.co.uk/2/hi/science/nature/4679220.stm that Physicists in Cambridge now know a lot more about dark matter than they used to. Here’s Professor Gary Gilmore’s philosophical summary of the discoveries.

bq. These are the first properties other than existence that we’ve been able determine.

HT: “Huw Price”:http://www.usyd.edu.au/time/price/

The “announcement”:http://myweb.facstaff.wwu.edu/nmarkos/BSPC/BSPC7/BSPC7.htm and “call for papers”:http://myweb.facstaff.wwu.edu/nmarkos/BSPC/BSPC7/Guide.htm for this year’s Bellingham conference are now up. This is always one of the more enjoyable conferences of the calendar, as well as being philosophically enlightening, so I’d encourage everyone to inundate the “paper submittee”:http://www.sitemaker.umich.edu/egana with submissions.

I once tried to put together a philosophy trivia quiz together. It was mildly successful, but now that I’ve seen what a “really well done (if somewhat prurient) philosophy trivia quiz”:http://web.mit.edu/philos/www/triviaquiz06/ looks like, I’m glad I won’t be trying again.

This quiz really is the ultimate procrastination device. There are 138 questions to test your knowledge of the history of philosophy and the histories of some philosophers. (I got at least one right – I knew question 12!)

Anyone with sufficient time on their hands is welcome to “try the quiz”:http://web.mit.edu/philos/www/triviaquiz06/ and leave a note in comments saying how many they got right.

Hat tip: “Alex Byrne”:http://web.mit.edu/philos/www/byrne.html