Re: RT list: Is it right to think about RT as a materialising theoretical attempt?

Malfet wrote:
> Chess is a quintessentially formal system. The universe of a chess game
> is composed of exactly 238 bits worth of information: 64 squares, each
> bearing either one of twelve classes of piece or no piece, plus a single
> boolean value to declare whether it is currently black's turn or white's
> turn. We can perfectly describe a chess game in these terms because it,
> as a system, is self-reducing...

Though free to choose his example, Malfet picked one that was not quite
accurate for his purpose.

The "bits of information" about what is located where on the chessboard,
together with knowing whose turn it is, are NOT sufficient to "perfectly
describe" a chess situation. In chess, you still need to know a little
bit, not just about the current state of affairs, but also what we could
call the position's "derivational history."

(This is due to the en passant rule in chess. Imagine that white has a
pawn on b5, and black has one on c5, and the squares c6 and c7 are
empty. Then, without more knowledge of the moves that led up to this
situation, we cannot know exactly what moves are available to white. He
might, or might not, be allowed to capture the black pawn by moving his
own to c6, depending on whether the game's previous moves enable the en
passant rule.)

We human beings are funny. We make up a game like chess
(quintessentially formal, says Malfet), but we also give it the en
passant rule. And over the centuries, we do not abolish that messy
rule. How vastly greater are both the formality, and also the
extra-formality, embodied in human language!

Hanno Beck
Received on Mon Sep 24 23:36:33 2012