Ads for The Imitation Game were everywhere, inspiring this post, during the weeks preceding its release. However, this Alan Turing-centric movie leaves out, for the masses, one important thing: the chess. Alan Turing, according to chessgames.com, wrote a chess program:
“…working with his former undergraduate colleague, D.G. Champernowne, Turing began writing a chess playing algorithm. In 1952, lacking a computer powerful enough to execute the program, Turing played a game against Alick Glennie, in which he simulated the computer, taking about 30 minutes per move. The program lost that game, although it is reported that it scored a victory against Champernowne's wife.”
Although the computer would not function due to the lack of processing power, Turing used a paper and pencil to carry out an algorithm, part of which is reproduced here:
“Point Values for Material: Pawn=1, Knight=3, Bishop=3.5, Rook=5, Queen=10
Mobility: For the pieces other than Kings and pawns, add the square roots of the number of moves that the piece can make, counting a capture as two moves.
Piece safety: If a Rook, Bishop, or Knight is defended once, add 1 point; add 1.5 points if it is defended twice.
King mobility: Use the same method as above, but don’t count castling.
King safety : Deduct x points for a vulnerable King, with x being the number of moves that a Queen could move if it were on the same square as the one occupied by the King.
Castling: When evaluating a move, add 1 point if castling is still possible after the move is made. Add another point if castling is immediately possible or if the castling move has just been performed.
Pawn credit: Score 0.2 points for each square advanced, plus 0.3 points for each pawn defended by one or more non-pawns.
Checks and mate threats: Score 1 point for the threat of mate and a half-point for a check.”
This computer was called Turochamp, and operated using the above algorithm: a simplified version of a human player’s thoughts when playing. Several important techniques, such as the adding and subtracting of numerical values for different considerations, which computers today use, were thus pioneered.
The computer’s (operated by Turing)* game against Alick Glennie, perhaps technically the first human-computer game:
*This unit to be henceforth referred to as, simply, Tur.
At the Turing Centennial in 2012, Kasparov played the engine (now able to be run), giving it ten seconds per move (2 ply):
Although Turing’s program is weak, it advanced chess–and is worthy of mention.
Paul Leggett
