Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Isn't it an easy case?

Author: Alastair Scott

Date: 05:15:53 12/01/03

Go up one level in this thread


On December 01, 2003 at 08:01:28, Gabor Szots wrote:

>If an engine is unable to claim draw on repetition, then it is not a draw if the
>opponent plays on. Not a draw even if the same position repeats 10 times.
>If the GUI claims the draw, it is as if a spectator would have claimed it,
>therefore invalid.

The problem with this argument is that it leads to indeterminate results because
GUIs might not just "claim"; they might do (or not do) something which
materially affects the progress of the game.

Suppose program A doesn't know about three-fold repetition, or has a bug which
prevents detection, and program B stops immediately it detects a three-fold
repetition.

What could happen, as a result, would be:

A misses the repetition and makes a move;

B stops;

A sits there, waiting for a move in response;

B will never move;

(Eventually) A stops because it thinks it has won on time.

So what is the eventual result ... ? In this sort of situation it would be a
Solomonic judgement by a human arbiter ;)

30 years ago there must have been far more such problems as "the art of chess
programming" was not as advanced; I remember, in the early 1980s, programs which
were unaware of three-fold repetition, the 50-move rule and underpromotion! What
happened then? (I strongly suspect a shrug of the shoulders; unlike now,
everything was confined to academia and there was no money involved).

Alastair



This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.