On today's show (i.e., Sunday January 28, 2007) Ken and I will interview Harry Frankfurt, Professor Emeritus at Princeton University.  Frankfurt has been around a long time, even longer than me, I think.  He has written important work on Descartes and the Cartesian Circle (see Demons, Dreamers, and Madmen, 1970), freedom and free will (see Freedom of the Will and the Concept of the Person in the Journal of Philosophy, 1971)  and related issues  of caring, love, identity and much else (see The Importance of What We Care about: Philosophical Essays, 1988, Necessity, Volition, and Love, 1999 and Taking Ourselves Seriously & Getting It Right,  2005).  Today we'll focus on, or at least begin with, his two best-selling little books, On Bullshit, 2005, and  On Truth,  2006.  The first decries and  defines  bullshit; it assumes we care about the truth, the second  tells us why we should.

Philosophy literally means "love of wisdom," or so I am told.  Modern analytic philosophers might find "wisdom" a little pompous, and prefer "love of truth" as an articulation of the central aim of philosophers.  Of course, love of, or devotion to, truth, is not peculiar to philosophy.   But still, it is a central aim.  But philosophy is also, as we like to say on Philosophy Talk, devoted to questioning everything (except your intelligence), then we are committed to questioning the central aims of philosophy, including truth, and the value of questioning everything.

Frankfurt makes the point that truth is often of practical significance.  This is certainly true in life's mundane affairs.  If I want to show up for the program on time, it's better that I think that it will start at 10 a.m., when it will start, than 11 a.m., by which time it will be over.  If I want to drive there, it's best if my gas gauge is correct, so that I don' t think my tank is full when it is empty.

It's also true about  some not-so mundane things.  Bush invaded Iraq thinking they had weapons of mass destruction.  Since then we've been told that the fact that this wasn't true wasn't important.  Bush said he would do it all over again, even if he knew then what he knows now; even Kerry couldn't make up his mind whether knowing what he knows now would change his vote.  So much the worse for the thought processes of Bush and Kerry.

A distinction worth making, I think, is between cases in which the truth is important because the subject matter involved is itself important, independently of whether people know or care about it, and cases in which the truth is only derivatively important, because philosophers or others care about it, and if we get something wrong we will be in some sort of trouble with these people.  It matters if the earth is getting warmer, particularly if there is something we can do about it.  This was so, before we realized it was getting warmer, and it would be so, even if we hadn't figured it out yet.  It is the warmng of the earth that will have many effects on human life, which if we know the truth we may be able to prevent, or at least prepare for.

But consider the fact that Locke's chapter on personal identity only appeared in the second edition of his Essay.  That's important to me.  It means we can't appeal to his theory of personal identity to explain other parts of his Essay, that already appeared in the first edition.  If I don't know this fact, I may say something stupid about the Essay.  Other Locke fans may think less of me.  And so forth.  The negative effects  not knowing the truth don't stem in any direct way from Locke and his writings, but from the fact that other people care about getting the facts about Locke right.

Once there was a scholarly debate about whether Berkeley suffered from chronic constipation.  A whole book was written on this subject, and it provoked many articles.  Berkeley's chronic constipation, if he had that problem, was important to him, and knowing the truth about it may have been important to the folks that dealt with him --- tar water merchants and the like.  But whether he did or not had no effect on anyone who took part in this debate.  All that mattered was that they and other people were curious, and cared one way or another.

If we are honest, it seems we'll have to admit that much research in the humanities has to do with topics about which the truth is of no direct importance; it has only this indirect importance, because people have come to care about it, for some reason or another.  And, I suspect, much research in mathematics, especially topics like large cardinal theory, also has this characteristic.  And frankly, I suspect that this is too of a great deal of science.  It's really cool that we are discovering the truth about whether there was ever water on Mars.  Perhaps its directly important, because someday we  will have colonies on Mars, or something we learn about Mars, that turns on whether there is water there, will lead to a cure for cancer or athlete's foot or God knows what.

Be that as it may, I don't think the money we spend on finding out whether Mars has water could be justified on a hard-nosed cost benefit analysis, any more than the (very modest) amounts we spend on learning minutae about the composition of the works of dead philosophers or novelists could be.  The truth about these things is most likely only important because people care about it. 

Sometimes philosophers and others, who love truth, and the search for truth, seek a more solid foundation for their enterprizes than that they care about the truth of the things they do research about it, and so do other people.  The search for truth becomes the true calling of humankind, the ineluctable denstiny of the Human Spirit, or something like that.  At that point, lovers of truth become purveryers of bullshit. 

Or so it seems to me right now.  Insight?  Or chronic constipation?