Not much blogging for the next week or so while some other matters are attended to. There are some very interesting comments threads below that I would like to jump into, especially on the preface paradox, but in practice probably won’t over the next week. Maybe when I return.

Yesterday the blog got spammed by some company offering new blogging software. Naturally, they got added to the spam block list. I think the effect of this is that anyone using their blogs will also be on the ‘do-not-accept-links-from’ list, which is a bad-making feature of a blog software supplier. Dumb spammers.

Unexpected First Lines

David Chalmers has persuaded Frank Jackson to post many papers to the Centre for Consciousness website. One of them is Frank’s review of James Franklin’s Corrupting the Youth: A History of Philosophy in Australia. It starts with the following line.

Philosophers are reluctant to take time off to do history, even the history of their own subject.

Now I know history of philosophy is not a big part of the mission at the Research School, but I never knew it had completely dropped off the radar screens!

I remember when this came out in print someone (and I can’t remember who) suggested the best interpretation was that he meant contemporary history, which would be relevant, given Franklin’s book, and make the claim true. So that’s the natural charitable interpretation. But as novel and unexpected sentences go, this one was fairly novel and unexpected.

Tractatus in Music

I was listening to the Bloc Party album while grading an exam, and noticed one odd lyric in Little Thoughts.

The world ain’t just made of facts.

This looks like a bald statement of an anti-Tractarian metaphysic, which is perfectly reasonable in and of itself, but somewhat out of place in a pop song. As you can see from the rest of the lyrics there’s not a lot of context to get clear on exactly what they meant. (I linked to a Google page so you can choose which pop-up infested lyrics site you want to go to.)

I guess the Police did borrow an album title from Gilbert Ryle, so maybe the New Wave revival will also spark a revival of interest in British metaphysics among pop stars.

Real Prefaces

As mentioned in a couple of posts below, my view is that it isn’t required of an author, even a sincere author, that she believes everything she writes in a scholarly work. When I say that’s my view, do I mean I believe it? Well, I think it’s probably roughly true. Good enough for scholarship. If I had to wait for belief, I might not write anything. Since we reward people who don’t wait for belief, it doesn’t seem like the community of scholars doesn’t take belief to be a norm governing scholarly assertion.

But I do think in some contexts you should only say what you believe. Writing a travel guide, for instance, probably requires belief in each claim you write. So a preface paradox involving a travel guide would be more impressive to me than a preface paradox involving a scholarly work. So I decided to see if I could find a real life case of this. For better or worse, I only stock Lonely Planet guides. (I have to support businesses from the eastern suburbs you see!) And they basically don’t include anything like a prefatory comment saying there are mistakes.

Well, that’s a little misleading. They do have the following comments. First under the heading WARNING & REQUEST.

Things change – prices go up, schedules change, good places go bad and bad places go bankrupt – nothing stays the same. So, if you find things better or worse, recently opened or long since closed, please tell us and help make the next edition even more accurate and useful.

This does suggest there will be mistakes, but also implicates (at least) that all the mistakes are due to the world changing since the book was written. That is, there is at least an implicature that the book was correct at some time. (Perhaps the time of writing, not even necessarily the time of printing.) The only thing that would make me qualify this claim is on the next page.

Guidebooks are not intended to be used as if they provide a detailed set of infallible instructions.

But I think it is clear from the context that they are not saying some of their factual claims might be mistaken, but rather that the good tourist will choose their own plan of attacking the holiday, rather than following the book’s suggestions.

The statements from the authors at the start refer to the fact-checkers, but don’t make any claims that there are still mistakes left. (At least the ones I have to hand don’t – I don’t claim to have checked them all.)

So Lonely Planet books don’t go as far as Wittgenstein as saying that everything in the book is correct, but unless I’m missing something, they don’t have any claim to the effect they may include mistakes. This is all to the good, because they don’t have one of the excuses scholars have for making such claims.

I’d be interested to know if other travel guides are as immodest. (If they are not I’ll take that as another sign I should stick with the Australian books!)


If you have actual work to do (grading, writing papers for deadlines, remembering to prepare food, etc) I wouldn’t recommend reading the rest of this post. For the braver among you.

After reading this story in the Guardian I lost a lot of time yesterday playing Sudoku. It’s basically a magic squares game from Japan, that seems like it should be easy, but is in practice surprisingly hard. And surprisingly addictive. I didn’t get to the point where I’d stop watching a Red Sox game in order to keep playing, but I did manage to procrastinate on some grading in order to keep playing. (I guess that doesn’t really tell you much about the addictive effects.) Anyway, if you want to get no work done the next month, follow either of those links and you’ll have plenty of ways to avoid doing anything else.

Christensen on the Preface Paradox

I’m reading through David Christensen’s interesting Putting Logic in Its Place. Christensen is on the side of those who think that the Preface Paradox shows that deductive cogency is not a constraint on rational belief. He responds to several arguments to the contrary, of which I think the most interesting is what he calls the Argument Argument. This is, roughly speaking, the view that deductive cogency has to be a constraint because otherwise we couldn’t explain the force of deductive argumentation. (This is rough because as stated the argument, or at least the arguer, looks poised to confuse inference with implication. I think a version of the argument that doesn’t make this confusion can be given, but that’s for a later post.) After some back-and-forth that I won’t repeat, Christensen gets to the following worry.

Suppose, for example, the author of a history book were to discover that the claims in the body of her book formed an inconsistent set. Intuitively, wouldn’t this be very disturbing? … It is hard to see why an author should be more concerned by an inconsistency within the body of the book than with preface-style inconsistency … But wouldn’t discovering inconsistency among the individual historical claims always actually be highly disturbing?

This looks like a fairly serious concern to me. But Christensen dismisses it in a rather odd way.

What the defender of cohency needs to make his point is a case involving an inconsistency that necessarily involves a great number of the huge and diverse set of historical claims making up the body of a book, and for my part I know of no case in which we’ve had experience of this sort of discovering in actual inquiry … Until persauive specific examples are found, then, it seems to me that we’ve been given no good reason to think that deductive cogency requirements play an important part in epistemic rationality.

There are two interpretations of this, and both of them seem odd to me.
Continue reading “Christensen on the Preface Paradox”


As many of you will have read over at Brian Leiter’s that Benj and Jessica are leaving from here for Toronto. (By here, I mean Cornell in Benj’s case, and my block of Marshall St in both cases – they live about 50m away.) This follows up Delia and Mike leaving for Princeton a couple of months ago.

These are obviously big philosophical losses. But I wanted to use this space to make a few non-philosophical comments. As anyone who has moved, especially overseas, knows it can be a very disorienting experience. But moving here to Cornell was much easier than I would have expected it to be, largely because of how helpful the my new colleagues were. And Delia, Mike, Benj and Jessica were all incredibly helpful. If their new colleagues provide as much help to them as they did to me, they will feel very lucky indeed!

Of course, it’s not like they stopped being good friends, colleagues and neighbours once I’d settled in. I won’t bore you with more anecdotes, but suffice to say we here at TAR will miss them all very much.

But this is a philosophy blog, so let me add one philosophical point. When I was teaching Concept of Mind I was struck by one feature of Ryle’s argument against sense data. Ryle compares sense data to pictures on a movie screen, and then using some fairly undeveloped theories of what goes on when watching a movie, concludes that sense data can’t do the work they are designed to do. It struck me at the time that there could be some potential for defending sense data by using Ryle’s analogy, but supplementing it with a more sophisticated theory of psycho-aesthetics. The idea didn’t get much further than that, because I didn’t have the foggiest idea how one might carry out this project.

Then lo and behold, at a paper in the department a couple of weeks ago, Benj set out a worked out theory that deployed (among many other nice ideas) this device. The paper is available online here, and it is very nice paper indeed. I’m not sure I agree with all of Benj’s conclusions. He wants to develop an analogy with Richard Wollheim’s theory where one sees represented objects in photographs or paintings. I’m tempted by the more radical (i.e. blank-stare inducing) view of Kendall Walton’s that we see represented objects through photographs (but not paintings). Given that sense-data theory is rather unpopular these days, and Walton’s theory of photography gets about as much support as Lewis’s theory of possible worlds, I suspect this combination wouldn’t win many friends, and there is more future in doing things Benj’s way. And as I said, he has a very well worked out theory, not just a hunch about how aesthetics might be relevant to philosophy of mind.

This paper of Benj’s is a very strong defence of a theory, sense-data theory, that doesn’t get enough positive attention nowadays, and I highly recommend reading it.

Preface Paradox

I’ve been reading a little bit on the preface paradox, so what I say in the following might be unoriginal. I doubt it is false however.

The standard way of setting up the preface paradox is something like the following. A historian writes a book. It includes, let’s say, 4000 sentences, each of them (we’ll assume for sake of argument!) expressing a proposition. She is careful with writing the book, and it is natural enough to say she believes each of the propositions in it. Call these P1, P2, …, P4000. In the preface she writes something like the following.

Despite my best efforts, I’m sure that this book, like all books, contains some mistakes.

The thought is that she’s now contradicted herself, because she has said each of the following.

P1, P2, …, P4000, ~(P1 & P2 & … & P4000)

But it is really unclear that she has asserted these things, or believes them, which is what’s really at issue. What she said was that there is a mistake in the book. Now it is true that the book is (among other things) the conjunction of P1 through P4000. (“Among other things” because the book also contains claims about evidential relationships between the claims.) But from that it doesn’t follow that she believes that one of P1 through P4000 is false unless she believes that P1 through P4000 are the propositions in the book.

(Actually even that isn’t enough – she also needs to infer from the falsity of something in the book and the fact that what’s in the book is is P1 through P4000 that one of P1 through P4000 is false. One of the standard ways to resolve the preface paradox is to deny that beliefs have to be closed under conjunction. It is noticable that even deniers of closure assume closure in setting up the puzzle.)

To be sure, the author did write the book, so in some sense she knows what is in it. But if the book is long enough to get a prefatory warning of falsity, it isn’t clear that the author needs to remember everything is in the book. At best, what she could remember is what she intended to write. She can hardly remember her own typos that went uncorrected, or misprints. But in reality she probably can’t remember all the intentions either. (I hardly remember the start of this post, let alone the start of a 300 page book.)

What is unclear to me is how far this goes to solving the preface paradox. I’m half inclined to say that it entirely solves it. A rational author who knew exactly what they said, and believed every claim in the book, would not take any of it back in the preface. Real authors are not like this – they are forgetful.

UPDATE: I should research first, write second. The main point I’m making here has already been made – in a paper by Simon Evnine “Believing Conjunctions”, Synthese 118: 201227, 1999. This isn’t to say I agree with everything Evnine says, but he does make this point first, or at least before me!