Player Hatin'

There has been a lot of buzz going around the blogs lately about the question of whether or not Deep Blue's just-now 10 year old victory against Gary Kasparov is significant in any way. This discussion was kicked off by an article by Tufts philosopher (and Santa Clause look-alike) Dan Dennett in this month's Technology Review. Dennett, predictably enough, takes a vaguely Quinian approach to this question--he wants to deny that it is even an interesting question to begin with. To Dennett, the question of whether or not computers are or are not better than humans at chess is only a question because of some wrongly held (and, Dennett implies, rather naive) beliefs about the uniqueness of our own brains. The intuition driving the idea that Deep Blue didn't really beat Kasparov, Dennett contends, is based in the notion that Deep Blue's processes while playing chess were so radically different from Kasparov's that the machine's victory didn't rightly deserve the title. Dennett argues that this intuition is wrong, and attempts to show that the functional processes that Kasparov and Deep Blue went through in preparation for each move were (functionally) equivalent; Deep Blue no more engaged in pure "brute force" computation than did Kasparov.

While I'm not convinced that Dennett is right, I'm willing to grant him this point, as I don't think it is the crucial one that ought to be examined. Dennett, like many philosophers working on this problem, overlooks an even more basic question that must be answered before the question of whether or not Deep Blue's victory is significant: was Deep Blue playing chess in the first place? Note the difference between this question and the one that Dennett asks: I'm not asking about how Deep Blue plays chess, or arguing that its approach to the game is different from Kasparov's to a significant degree--I'm making a much stronger claim. This claim, put simply, is just the following: machines don't play games in the first place, so Deep Blue (while an impressive achievement certainly) didn't prove anything by "winning" the match with Kasparov; Deep Blue was never in the match in the first place.

I know that I promised reasonably short posts on this blog, but I think this claim deserves at least some explanation, considering the fact that virtually everyone disagrees with it. Why wasn't Deep Blue playing chess? After all, it was making moves that were constrained by the rules of chess, and it was playing the same functional role in the match that a human grandmaster would have played in a normal chess match--surely this is good enough? Even asking this question flies in the face of the conventional wisdom; virtually every blogger covering this story has sought to address whether or not Deep Blue's victory over Kasparov says something significant about Deep Blue's intelligence--my position is that Deep Blue didn't really win anything, because it wasn't playing in the first place.

Playing a game like chess is an inherently social activity--it requires the participation of two (or more) entities that are capable of playing the game intentionally. Ignore, for the moment, games like solitaire. We'll get to that later. Suppose you and I sit down at a chess board, but without knowing what it is (or how to use it). We decide to pass the time by taking turns moving the pieces around the board randomly. It just so happens that each of the moves we make corresponds to the actual rules of chess, but this is totally accidental--we had no intention to move them in this way. It seems to me that, though we're certainly doing something, we're not playing chess; there must be more to the game than acting in certain ways or fulfilling certain functional roles.

The case gets stronger, though. Playing a game like chess requires the capability to create meaning, and that in turn requires the capacity to represent. Without getting too much into the technical details, there are some pretty compelling reasons to believe that this is something that machines just cannot do. When you and I play chess, we're doing something more than just shuffling piece around a board. We're even doing something more than shuffling piece around a board according to prescribed rules. The difference, at least as I see it, between Kasparov and (say) Bobby Fischer playing a game of chess and Kasparov and Deep Blue "playing" a game of chess is that in the former scenario both participants are conscious entities and intentional participants in the game. In the latter case, one is conscious and the other is (by definition) not--try and guess which is which!

Once again, this is not a point about how Kasparov and Deep Blue play chess; whether or not someone is a participant in a game has virtually nothing to do with their strategy for that game. It is entirely possible that a chess savant might one day be able to "brute force" calculate moves in the same way that Deep Blue does--would that mean that the chess savant was not playing chess? Certainly not. Once again, the defining attribute of a game is intentional participants.

This is even more clear if you think about two computers "playing chess." Suppose we network Deep Blue and Deeper Blue and let them have at each other. Electrical signals fly back and forth across the connection medium, and both machines are processing at full power. Are they playing chess? From the perspective of the computers (such as it is), there's no difference between playing chess, playing tic-tac-toe, holding a conversation about the weather, or working together to solve an equation. In all cases, the machines' actions just boil down to mathematical computation or (at an even lower level) electricity flowing over wires.

Summing up: the salient question here is not whether or not Deep Blue's victory is significant for artificial intelligence, and it is not whether or not the fact that Deep Blue's approach to a chess problem is different from Kasparov's is significant. The question we should be asking is whether or not machines can be participants in games at all, and the answer to that question seems to me to be a resounding "no." More on this later, probably.