First variant game of chess played by a computer

What was the first variant game of chess played by a computer — a simplified version of the game scaled down so the earliest number-crunching systems could actually handle the analytical demands?

The answer is Los Alamos Chess (sometimes called anti-clerical chess), played on a six-by-six chessboard, rather than eight-by-eight. Named for the Los Alamos National Laboratory in New Mexico, the birthplace of the atomic bomb, this version excludes bishops.

In 1956, scientists at Los Alamos used this chess variant as the basis for the world’s first chess computer program, written for the MANIAC I computer. To completely scale back the game for the benefit of MANIAC I, the game excluded en passant capture, two-position pawn openings, and castling as possible moves.

The Los Alamos Chess program, written by computer scientists Paul Stein and Mark Wells, apocryphally ran only three times. On the first run, the computer played itself. On the second, the computer played an unnamed but supposedly skilled human opponent, who defeated the machine. On the third run, a chess novice faced off against MANIAC and lost.

The program was largely a proof of concept, validating the theoretical possibility of a chess-playing program as proposed by such visionaries as Norbert Wiener and Alan Turing. It wasn’t until 1958 that someone wrote computer programs to play full, true games of chess, though precisely who wrote the first such program is a matter of some debate.

In 1967, the Mac Hack Six computer program became the first to defeat a human being in tournament play. In 1970, the ACM North American Computer Chess Championships formed, as there were enough competing chess software efforts to face them off in a traditional chess tournament. Four years later, an international equivalent tournament formed.

Thus, for more than 30 years, computers have been just as busily playing chess as their human adversaries, and in the last 10 years — starting with Deep Blue’s 1997 six-game defeat of Gary Kasparov — computer grandmasters have proven the equal or better of reigning human champions. That’s not just some game-changing computational power - it’s also a great gambit of Geek Trivia.

Category: Computers in Chess