I was browsing around Matthew Yglesias’s blog, wondering why I don’t have him on my list of permanent links yet for posts like this one, when I came across a philosophy paper he wrote about David Lewis’s On the Plurality of Worlds. David died unexpectedly a year ago last Sunday. He was Laurie’s adviser and, over the course of our time at Princeton, we were lucky enough to have him and his wife Steffi become our friends. His obituary in the Guardian gives some sense of his enormous contribution to analytic philosophy. Remarks from his memorial service by Laurie, Dave Chalmers, Philip Kitcher, Mark Johnston and David Armstrong tell you something of the standing he had amongst—and the impression he made upon—philosophers.

I don’t normally write about this sort of thing here, but Matthew’s paper set me off. It’s about the “incredulous stare”—the look of sheer disbelief, perhaps mixed with ridicule, but unaccompanied by any substantive counterargument, that David was sometimes confronted with when he presented his program of modal realism. “I do not know,” he would say, “how to refute an incredulous stare.” Amid the sophomoric snideness that passes for argument in much of the Blogsphere (with “Fisking”, name-calling, and all the rest of it), it’s good, though also sad, to stop and remember someone who could out-think and out-argue pretty much anybody, and yet who didn’t have a point-scoring bone in his body. David argued to get the right answer, not to get ahead. He wanted—in Geoffrey Warnock’s words—“to be clear-headed rather than confused; lucid rather than obscure; rational rather than otherwise; and to be neither more, nor less, sure of things than is justifiable by argument or evidence. That is worth trying for.”