Tuesday, June 23, 2009

Protagoras Goes To Wall Street

I've gotten a lot of reaction to my story about Nassim Nicholas Taleb, which is not surprising, because he has a lot of followers. In looking over the story, I feel like I made one point a little too equivocally. So I'll put it more strongly here: Taleb's general approach, as far as investing goes, is a losing strategy. Maybe times have changed, and we are in a protracted period of increased flux and unpredictability. But in general, historically Taleb's strategy of effectively buying insurance and waiting for a crash has been a loser. And I would add that I suspect it's especially likely to be a losing strategy at points when the rest of the world is running to safety and it is no longer contrarian.

There's another point, thought, that comes out of reader's letters and comments that's more interesting. Many Taleb fans wrote or commented to say that, hey, I just don't get Taleb's philosophy. As one commenter wrote, "He is totally against those making predictions. He laughs at them." Well, I do get that. The thing about Taleb is that he wants to get credit for his good calls, and at the same time he wants to be seen as making a broader philosophical point about the nature of prediction and expectation. It's that second part that gets a lot of people very excited, and they see some really deep thinking there. But it's all not nearly as new as a lot of Taleb's fans believe. It falls in a skeptical tradition going all the way back to Protagoras, who was supposed to teach his students to argue both sides of an issue with equal vigor, and has branches that stretch out not just to Karl Popper, the philosopher of science, but to Jacques Derrida and deconstruction.

Taleb talks about "prediction" where others talk about "truth," but the basic philosophical game of first undermining the received wisdom and then turning the skeptical view around and undermining your own claims is very old, and still very exciting when you first see it.The best practitioners are those who can play it longest without getting pinned down. But it is a game, and eventually it ends. Either you do get pinned down with "truths" or "predictions," and it loses its interest. Or you you don't, and eventually your followers get bored and go back to all the received ideas they'd so wholeheartedly abandoned and trying to remember what all the fuss was about.