The Chess Variant Pages



Infinite Chess

Dr. Cliff Pickover, author of many books (see his website: www.pickover.com) mentions in one of his books the chess variant Infinite Chess. This variant has been proposed by Tim Converse from the University of Chicago.

In December 2000, an email was sent to The Chess Variant Pages by Jianying Ji about Infinite Chess. His variant is slightly different from the one, mentioned by Pickover.

The board

The board is still 2-dimensional, but in all directions considered to be infinite. The standard board is considered to be the middle of the infinite plane. So the starting position is as follows:
   .        .          .
    .       .         .
     .      .        .
      r n b q k b n r
      p p p p p p p p
      . . . . . . . . 
...   . . . . . . . . ...
      . . . . . . . .
      . . . . . . . .
      P P P P P P P P
      R N B Q K B N R
     .      .        .
    .       .         .
   .        .          .

Converse's rules

In the variant, mentioned by Pickover, rooks, bishops, and queens may go as far as they want in the directions they can go. Other rules are the same as in FIDE chess.

Comment

Knights and pawns become relatively unimportant in this variant.

Ji's rules

In the variant of Jianying Ji, the rules are as follows:

All pieces moves as in FIDE chess, except the following stipulations:

  1. Knights are replaced with nightriders. (As compensation for the size of the board.)
  2. Pawns promote when it moves to a rank beyond which there are no enemy pieces.
  3. For each piece there must exist a 8x8 square which includes at least one piece of the opponent.

Consequences

So, for example, on the first move the white queen can't move back more than 1 space, because to do so would move out of any 8x8 square that contains opponent pieces.

Also the interplay between stipulations 2 and 3 makes pawn promotion much more interesting, there have to be much more consideration of where the opponent pieces are, including pieces that pose no threat to the promotion that can be used as cover to promote your piece.

In practice one doesn't need a infinite board, just a large enough board that can change shape. From stipulation 3 and the normal rules of chess someone probably could calculate what large enough is.

Comment

Jianying Ji writes:
Now I leave this game to the readers and hope they would find delightful tactics and deep strategies. I would appreciate any correspondence on new discoveries concerning this game.
His email address is: jianyingj at yahoo.com.
Webpage made by Hans Bodlaender, based on text written by Jianying Ji and an email from Cliff Pickover.
WWW page created: January 2, 2001.