I've previously blogged reading the first draft chapter of Peter Unger's Beyond Inanity. The draft chapters were up on his website, which is currently down, but check back there later, hopefully it will be back up soon. In this post, I'll be commenting on chapters two and three.
In these chapters, Unger delves in to exactly what parts of contemporary philosophy bother him. His central contention is that certain prominent philosophers, while purporting to offer concrete claims about the world, have only offered insubstantial ones (inane ones, in Unger's vocabulary). His first target is Donald Davidson's "Swampman" thought experiment, which imagines a man created by thermodynamic miracle. Davidson suggests that such a person, though by stipulation be an exact physical duplicate of some actual person, would have no beliefs, memories, friends, and so on. Unger's second target is Hilary Putman's claim that water could not possibly be anything other than H2O, so a person transported to a world where H2O was replaced by (superficially indistinguishable) XYZ would only make so many mistakes about thinking of that stuff as water. Finally, he takes on Kripke's claims about the essentiallity of origin, that an object could not possibly have originated in a different way than it in fact did and remain the same object.
Unger argues that these claims, if true, would fail to make any difference about the concrete world. I think it's pretty obvious he's right about this. Furthermore, it seems obvious to me that there is at least something strange about philosophy focusing on such insubstantial claims. But I think Unger makes some doubtful assumptions about how philosophers would likely respond to his criticisms. He seems to assume that fans of Davidson, Putnam, and Kripke believe their claims are concrete and would be embarrassed to admit they are insubstantial. I suspect, though that these philosophers would continue insisting on the importance of these claims in spite of their insubstantial nature. For one thing, philosophers often talk about abstract objects, which by definition aren't concrete, yet they seem to think it terribly important to understand abstract objects correctly. Mathematical objects are taken to be abstract, yet mathematics is important, that is one argument philosophers might use to justify their position. Philosophers have also long worried about understanding properties, which are also taken to exist as abstract objects. And some of the ideas that Unger dismisses as too absurd to be what philosophers have in mind, I unfortunately suspect they may have them in mind. Unger tries to deflate Kripke's claims about the origin of tables by inventing terms like "lables" (lot to be confused with "labels") and comparing the nature of tables with lables and such. Kripke suggests that no one could think that the essence of tables exists in any deeper sense than the essence of "lables," though after reading many of the philosophers he talks about, I wonder.
In spite of these criticisms, with more work on what Unger's targets are trying to say (and I don't claim to really understand them), I think Beyond Inanity could turn out to be a very interesting book.