Re: Transactions: good or bad?

Bob Badour wrote:  

> Where is your proof that all chess games halt?

For this I have a comment. For the rest of this argument, I'm staying the hell away.

The rules of chess allow the side to move to CLAIM a draw if either of the following occur:

1. The same position occcurs for the THIRD time (I saw a mistaken claim that a single repetition caused a draw).
2. Fifty moves occur without either a pawn being moved or a piece taken.

With these rules taken literally, a chess game can be infinite. Each side can play the same two moves repeatedly, and if neither claims a draw, the game doesn't halt. E.g.:

1. Nf3 Nc6
2. Ng1 Nb8
3. Nf3 Nc6

etc..

If the rules were changed to remove the option -- i.e., change the "may claim" to "shall claim," then a chess game becomes finite, and always halts.

Larry Coon
University of California
larry_at_assist.org
and lmcoon_at_home.com Received on Fri Jun 20 2003 - 23:54:49 CDT