I’m teaching a seminar on David Lewis in the spring, using Daniel Nolan’s book as one of the texts, but primarily using primary sources. (Note the link is now to Amazon US, not to Britain.) There’s one primary historical claim I want to make through the course, and I might post stuff here as I write it to try and back up this claim.

The claim is that concrete possible worlds aren’t that important to Lewis’s overall philosophy.

Now this might seem like a rather odd claim to make, since the existence of concrete possible worlds is the core claim of Lewis’s longest and most important book, and most summaries of Lewis start with this belief as the lead. So I’m swimming a little against the interpretative tide, such as it is at this early stage. But I do have something like an argument for my preferred interpretation, or perhaps better, preferred sense of what is central and what is relatively peripheral.

Although Lewis held fairly consistently to most of his views throughout his career, he was amenable to changing his mind in the face of good argument. He was constantly tinkering with the analysis of causation, he accepted some tinkering to the analysis of intrinsicness, and most importantly, he abandoned egalitarianism about properties. So we can coherently, even easily, imagine him changing his mind on some of his conclusions.

Now for any paper or work of Lewis’s, do the following thought experiment. Imagine someone giving him a convincing argument that the core conclusion of the paper failed, shortly after the paper appeared in print. Try to follow through then how many changes would have been needed to later work if he’d accepted this criticism, and hence not been able to presuppose the truth of his earlier claims.

In some cases the changes would be immense. It is almost impossible to imagine what Lewis’s work would look like if he didn’t have the Ramsey-sentence definition of theoretical terms, and his convention-based account of language to work with throughout. Similarly we would need massive revisions if he’d been convinced that Humean supervience was fundamentally flawed, or that egalitarianism about properties was true after all, or that one of the paradoxes from chapter 2 of Plurality was fatal to the possible worlds apparatus. These I think are the five core claims that Lewis’s philosophy is built around, and if he’d given any of them up, it would have forced massive revision to the rest of his work.

Not so for concrete possible worlds. If someone had written a version of ersatzism in 1987 that Lewis thought gave us all we needed from a theory of possible worlds, and wasn’t vulnerable to the chapter 3 objections, then he could have accepted it, and, more importantly, he would have had to make next to no substantive changes to anything else he wrote. What is of broad philosophical importance for Lewis (and others such as Stalnaker and Jackson are in this camp too) is that the possible worlds framework is coherent and applications of it can be philosophically enlightening. Lewis had opinions on the metaphysical foundations of that framework, but they weren’t central to the philosophical picture he gave us.

The test I’m using for importance isn’t perfect, because it isn’t clear always how to apply it. I’ve been deliberately silent in what I’ve said above about the importance of the analysis of counterfactuals and of causation to the picture, as it is being sketched here. I tend to think that in both cases the details (in some sense of detail) are not important, any more than the details of the account of intrinsicness or colour or dispositions or chance or laws are important. (Which is not to say they don’t at all matter – Lewis worked hard on finding reasons to support particular analyses of all of these.) But both causation and counterfactuals seem more central to the project than these other cases, especially counterfactuals. Saying just why I think that needs more work, and hopefully I’ll be able to have something more coherent by the time next spring rolls around.

I have a vested interest in this interpretation being taken seriously, because broadly speaking I’m a Canberra Credo guy, and “We [Credoers] believe in the substantial correctness of the doctrines of David Lewis about most things (except the nature of possible worlds).” It would be nice if (a) we could argue that this is a coherent position, which it isn’t if concrete possible worlds are central to Lewis’s picture, and (b) one which involves only a small deviation from Lewis’s theories, since it’s odd to look up to someone on so many matters while disagreeing with them about what is fundamental to their work.

Speakers at Cornell

We have talks each of the next three Fridays at Cornell.

This Friday April 1 we have Max Pensky of Binghamton University whose talk is titled “On Constitutional Law and Solidarity”.

Next Friday April 8 we have Rae Langton of MIT whose talk is titled “Objective and Unconditioned Value”.

And the Friday after that, April 15, we have Christopher Taylor of Oxford University (currently visiting at Cornell) whose talk is titled “Courage in the Protagoras and Nicomachean Ethics”.

All talks are in Goldwin Smith Hall at 4.30pm. Max Pensky is in room 134 and Rae Langton and Christopher Taylor are in room 142. I hope many people from the area can make these talks.

UPDATE: I forgot to mention two other talks in the Time and Tense seminar.

Next Monday Armin von Stechow will be doing a talk titled “Temporal Orientation of Modals and Covert Temporal Operators” at 4.30 in Goldwin Smith 134.

The Monday after that Peter Ludlow will be doing a talk titled “‘I Resemble Fitz Hugh Ludlow’: Presentism and the Problem of Cross-Temporal Reference”. It is April 11, 4.30pm in Goldwin Smith 134.

And it isn’t in the the philosophy department, but since it is a philosophy talk I should mention that von Stechow is doing another talk, this one on Tuesday April 6 at 4.30, in Morrill 106 called “Anankastic Conditionals”. Here’s the abstract.

Anankastic conditionals are constructions exhibited by the following paradigm:

a. You have to take the A train if you want to go to Harlem.
b. If you don’t take the A train you can’t go to Harlem.
c. To go to Harlem you have to take the A train.

They express the idea that the consequent is a necessary condition for achieving the goal expressed by the antecedent. The contstruction has been very reluctant to a compositional analysis. We will propose a counterfactual analysis. The truth condition arrived at is this:

d. The nearest worlds where you go to Harlem, are contained in the worlds where you take the A train and the nearest worlds where you don’t take the A train are disjoint from the worlds where you go to Harlem.

We will give a compositional semantics, which derives this.

We will compare our analysis with the analysis of Saeboe, von Fintel & Iatridou and Huitink.

Hoping and Wanting

Much to be said about San Francisco, testimony, contextualism, value-laden epistemology, horribly sad news from home and the assorted things that happen over a week. But instead of saying any of them I’ll just make one small grammatical observation. I’m sure this is something that most of you know, and it is well-investigated by linguists, but it was news to me. It’s surprising, from some perspectives, that (1) is grammatical while (2) is not.

(1) John wants Mary to win.
(2) *John hopes Mary to win.

There’s a certain kind of philosophical program (one that no one really adopts but which many people seem to feel the pull of) that wants (hopes?) to have all studies into psychological states be redrawn as studies into the syntax and semantics of words for psychological states. Now I don’t think this is an entirely bad idea. It’s important to learn that not all mental states are reducible to beliefs and desires, for example, and linguistic analysis of e.g. the notion of intention can suggest grounds for anti-reductionism.

But it can also go too far. It would be a very bad mistake to conclude from the distinction between (1) and (2) that there are these two mental states, wanting and hoping, such that one of them is an attitude towards the world and one of them is an essentially first-personal attitude. Sometimes a grammatical rule is just a grammatical rule, and this is one of those times. Just how often this mistake is made is I think a fairly interesting question.

Job Placement

A while back I did a small study on placement rates of top PhD departments. At the time I left out NYU because they didn’t have a record. Now they do have a record, and it is pretty good – 100% of graduates in good jobs, around half of them in jobs that are clearly great jobs. It’s a very small sample, but something for PhD candidates to consider when deciding between universities. (Thanks to Ned Block for the link.)

Law and Epistemology

In the comments to a thread a couple of entries down, Gideon Rosen makes the following point.

Note that in most legal contexts, knowledge means “true belief” or perhaps “true confident belief”.

As noted in the thread, there are some exceptions to this (e.g. insane people, perhaps beliefs about the future) but it seems to be largely correct. He goes on to say.

It never means knowledge in our sense.

I sort of agree. Relying on a philosophical analysis of ‘knowledge’ would get you laughed out of court in most cases where it mattered. But isn’t this a problem for epistemology? We’re meant to be analysing (or at least clarifying) the ordinary concept of knowledge. If in one of its most important uses, the law, the word ‘knows’ behaves totally differently to how we say it behaves, I think that’s a problem for epistemology. This looks like a project worth working on.

As also noted in the comments, Chris Green has a paper on law and epistemology on the program at the Pacific APA. Chris seems to take a different line to what I’m interested in – he uses some of the careful distinctions the law makes to try to adjudicate between different contemporary epistemological theories. I’m more interested in the idea that the law provides evidence that contemporary theories of knowledge are more radically mistaken, and that the law is right to say (as do some epistemologists, e.g. Hetherington and Sartwell) that knowledge is something like true confident belief.

Definitions of Knowledge

It’s easier than you think to define knowledge. Here’s the Massachusetts Rules of Professional Conduct Definition.

(f) “Knowingly,” “known,” or “knows” denotes actual knowledge of the fact in question. A person’s knowledge may be inferred from circumstances.

All us epistemologists can sleep easy now. (As noted in previous post, I’m all of a sudden very interested in how “knows” is actually defined at law, but I don’t think this is going to help.)

Lackey on Testimonial Knowledge

Ishani was just talking with me about Jennifer Lackey’s prize-winning paper and we noticed something odd about one of the core examples. Here’s the example, with the discussion after the fold.

COMPULSIVELY TRUSTING: Bill is a compulsively trusting person with respect to the testimony of his neighbor, Jill, in whom he has an obsessive romantic interest. Not only does he always trust Jill when he has very good reason to believe her, he is incapable of distrusting her when he has very good reason to not believe her. For instance, even when he has available to him overwhelming evidence for believing that she is deliberately lying or being deceitful, Bill cannot come to believe this about Jill. Indeed, Bill is such that there is no amount of evidence that would convince him to not trust Jill. Yesterday, while taking his afternoon walk, Bill ran into Jill, and she told him that she had seen an orca whale while boating earlier that day. Bill, of course, readily accepted Jill’s testimony. It turns out that Jill did in fact see an orca whale on the boat trip in question, that she is very reliable with respect to her epistemic practices, both in general and in this particular instance, and that Bill has no reason to doubt the proffered testimony. Given his compulsively trusting nature with respect to Jill, however, even if he had had massive amounts of evidence available to him indicating, for instance, that Jill did not see an orca whale, that she is an unreliable epistemic agent, that she is an unreliable testifier, that orca whales do not live in this part of the country, and so on, Bill would have just as readily accepted Jill’s testimony. Continue reading “Lackey on Testimonial Knowledge”

Rutgers Epistemology Conference

Via Certain Doubts, the schedule for the Rutgers Epistemology Conference is now online. Here are the papers.

And Keith has posted an updated version of his paper.