ChessGenius

ChessGenius is a chess-playing computer program written by Richard Lang, who has in the past written programs that have won the World Computer Chess Championship on 10 occasions.

[1] ChessGenius is a continuation of a series of programs (which included various incarnations of the Mephisto program[2]) written by Richard Lang which won the World Microcomputer Chess Championship in 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991 and 1993.

[3] ChessGenius was the first computer to beat a world champion (Garry Kasparov) at a non-blitz time limit.

[4][5] This victory was particularly significant because in contrast to the victory two years later by Deep Blue which was running on very fast custom-built hardware, ChessGenius was running on only an early Pentium PC.

[9] The built-in opening book for ChessGenius for Windows was written by a team led by Ossi Weiner.

[10] In an article comparing ChessGenius with Fritz in February 1994 Grandmaster and computer chess expert John Nunn wrote, "[m]y own opinion is that if raw playing strength is your dominant criterion, then go for Genius".

[12] ChessGenius, like many of Lang's programs, was famous for having an 'asymmetric evaluation function' which means that moves and sequences of moves might be scored differently depending on whether they are to be made by the program or by the opponent (which has implications for which lines are 'forward pruned' in its calculations).

[18] The programmer Richard Lang has suggested that this was because the program does not scale well to faster hardware.

[2] Portable versions (for example for Palm and the original iPhone) perform exceptionally well because ChessGenius is particularly strong in weak hardware environments.

[2][10][19] Unlike most other commercial vendors, Richard Lang explicitly forbids including the PC version of ChessGenius in chess engine rating lists,[citation needed] so it is difficult to gauge its strength compared to other modern programs.

It has been suggested that this branding (as "Classic") is also because apart from speed and efficiency enhancements, and updates to its openings book, the program has not changed dramatically since 1995.

This is the famous game from 1994 in which ChessGenius, playing with the black pieces, defeated the then world champion Garry Kasparov.

The game sees Kasparov rejecting clear drawing opportunities and eventually losing.

ChessGenius plays fairly well despite making some anti-positional moves which Kasparov was unable to capitalize on.

[6]White: Garry Kasparov   Black: ChessGenius   Opening: ECO D11 1. c4 c6 2. d4 d5 3.