Co-ordinate square: a solution to many chess pawn endgames

• Authors: Kenneth W. Church
• Venue: IJCAI'79 Proceedings of the 6th international joint conference on Artificial intelligence - Volume 1
• Year: 1979

The solution to a number of Artificial Intelligence problems depends upon Knowledge representation. The theory of Co-ordinite Squires is a frameworK for representing the relevant ideas in a large class of King and pawn endings. Some endgame problems which require twenty to thirty plies of analysis using a more traditional representation, a branching tree of moves, can be efficiently solved using this theory, which is analogous to Waltz, scene analysis algorithm. The Co-ordinate Squares theory, which has received considerable attention in the chess literature over the last half century, is Implemented using a constraint propagation technique. The constraint is that the defending King must precisely coordinate with the attacking King to avoid losing. For any particular square the attacking King occupies, there are only a few possible (co-ordinating) squares the defending King could occupy without transposing into a Known lost position. As the attacking king moves from one square to another, the defending king must co-ordinate, move from a co-ordinate of the one square to a coordinate of the other. We will give a reduction algorithm which propagates this constraint in order to determine the coordinate squares.