Turochamp,
a chess program by Alan Turing and David Champernowne developed in 1948 as chess playing algorithm, implemented as "paper machine". Since there was no machine yet that could execute the instructions, Turing acted as a human CPU requiring more than half an hour per move. One game from 1952 is recorded, which Turochamp lost to one of Turing's colleagues ^{[1]}, Alick Glennie. It won an earlier game versus Champernowne's wife, a beginner at chess ^{[2]}.

Turochamp incorporated important methods of evaluation^{[3]}, and also the concepts of selectivity and dead position, despite it is unclear how this was "implemented" in the game playing experiments. Champernowne later said 'they were a bit slapdash about all this and must have made a number of slips since the arithmetic was extremely tedious with pencil and paper' ^{[4]}. In a CCC forum post, Frederic Friedel mentioned a searchdepth of up to three plies^{[5]}.

Turing says that the system of rules set out in 'Chess' is based on an 'introspective analysis' of his own thought process when playing (but with 'considerable simplifications'). His system anticipates much that has become standard in chess programming: the use of heuristics to guide the search through the tree of possible moves and counter-moves; the use of evaluation rules which assign numerical values, indicative of strength or weakness, to board configurations; the minimax strategy; and variable look-ahead whereby, instead of the consequences of every possible move being followed equally far, the 'more profitable moves are considered in greater detail than the less'. Turing also realized the necessity of using 'an entirely different system for the end-game'.

The learning procedure that Turing proposed in 'Chess' involves the machine trying out variations in its method of play - e.g. varying the numerical values that are assigned to the various pieces. The machine adopts any variation that leads to more satisfactory results. This procedure is an early example of a genetic algorithm.

The Essential Turing

Champernowne's quote on Turochamp from The Essential Turing^{[8]}:

Most of our attention went to deciding which moves were to be followed up. My memory about this is infuriatingly weak, Captures had to be followed up at least to the point where no further captures was immediately possible. Check and forcing moves had to be followed further. We were particularly keen on the idea that whereas certain moves would be scorned as pointless and pursued no further others would be followed quite a long way down certain paths. In the actual experiment I suspect we were a bit slapdash about all this and must have made a number of slips since the arithmetic was extremely tedious with pencil and paper. Out general conclusion was that a computer should be fairly easy to programme to play a game of chess against a beginner and stand a fair chance of winning or least reaching a winning position.

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.

The mentioned game of Turochamp versus Alick Glennie, who wrote the Autocode compiler for the Manchester-Mark I computers. The game took several weeks ^{[14]}.

Alan Turing, Jack Copeland (editor) (2004). The Essential Turing, Seminal Writings in Computing, Logic, Philosophy, Artificial Intelligence, and Artificial Life plus The Secrets of Enigma. Oxford University Press, amazon

^ Chapter 16, Introduction on 'Chess', in Alan Turing, Jack Copeland (editor) (2004). The Essential Turing, Seminal Writings in Computing, Logic, Philosophy, Artificial Intelligence, and Artificial Life plus The Secrets of Enigma. Oxford University Press, amazon, google books

^ Chapter 16, Introduction on 'Chess', in Alan Turing, Jack Copeland (editor) (2004). The Essential Turing, Seminal Writings in Computing, Logic, Philosophy, Artificial Intelligence, and Artificial Life plus The Secrets of Enigma. Oxford University Press, amazon, google books

## Table of Contents

Home * Engines * TurochampTurochamp,a chess program by Alan Turing and David Champernowne developed in 1948 as chess playing algorithm, implemented as "paper machine". Since there was no machine yet that could execute the instructions, Turing acted as a human CPU requiring more than half an hour per move. One game from 1952 is recorded, which Turochamp lost to one of Turing's colleagues

^{[1]}, Alick Glennie. It won an earlier game versus Champernowne's wife, a beginner at chess^{[2]}.Turochamp incorporated important methods of evaluation

^{[3]}, and also the concepts of selectivity and dead position, despite it is unclear how this was "implemented" in the game playing experiments. Champernowne later said 'they were a bit slapdash about all this and must have made a number of slips since the arithmetic was extremely tedious with pencil and paper'^{[4]}. In a CCC forum post, Frederic Friedel mentioned a search depth of up to three plies^{[5]}.## Chess

In his 1953 paper 'Chess' in Bowden'sFaster Than Thought^{[6]}, Turing defines evaluation features, and elaborates on minimax strategy, variable look-ahead, quiescence and even learning as an early example of a genetic algorithm. He does not explicitly mention the name Turochamp, but the 'Machine', and its game versus a human. Jack Copeland inThe Essential Turing, 2004^{[7]}on Turing's paper:Turing says that the system of rules set out in 'Chess' is based on an 'introspective analysis' of his own thought process when playing (but with 'considerable simplifications'). His system anticipates much that has become standard in chess programming: the use of heuristics to guide the search through the tree of possible moves and counter-moves; the use of evaluation rules which assign numerical values, indicative of strength or weakness, to board configurations; the minimax strategy; and variable look-ahead whereby, instead of the consequences of every possible move being followed equally far, the 'more profitable moves are considered in greater detail than the less'. Turing also realized the necessity of using 'an entirely different system for the end-game'.

The learning procedure that Turing proposed in 'Chess' involves the machine trying out variations in its method of play - e.g. varying the numerical values that are assigned to the various pieces. The machine adopts any variation that leads to more satisfactory results. This procedure is an early example of a genetic algorithm.

## The Essential Turing

Champernowne's quote on Turochamp fromThe Essential Turing^{[8]}:Most of our attention went to deciding which moves were to be followed up. My memory about this is infuriatingly weak, Captures had to be followed up at least to the point where no further captures was immediately possible. Check and forcing moves had to be followed further. We were particularly keen on the idea that whereas certain moves would be scorned as pointless and pursued no further others would be followed quite a long way down certain paths. In the actual experiment I suspect we were a bit slapdash about all this and must have made a number of slips since the arithmetic was extremely tedious with pencil and paper. Out general conclusion was that a computer should be fairly easy to programme to play a game of chess against a beginner and stand a fair chance of winning or least reaching a winning position.## Evaluation Features

^{[9]}## Programming trials

At the University of Manchester, Turing began programming Turochamp, as well as Michie's and Wylie's program Machiavelli, to run on a Ferranti Mark 1 computer, but could not complete them^{[10]}. In 2004 ChessBase published a engine based on Turing's ideas, developed by Mathias Feist with the help of Ken Thompson^{[11]}^{[12]}^{[13]}.## Turochamp vs. Glennie

The mentioned game of Turochamp versus Alick Glennie, who wrote the Autocode compiler for the Manchester-Mark I computers. The game took several weeks^{[14]}.## Publications

1953).. part of the collectionChessDigital Computers Applied to Games, in Bertram Vivian Bowden (editor), Faster Than Thought, a symposium on digital computing machines, reprinted 1988 in Computer Chess Compendium, reprinted 2004 inThe Essential Turing, google books2004).The Essential Turing, Seminal Writings in Computing, Logic, Philosophy, Artificial Intelligence, and Artificial Life plus The Secrets of Enigma. Oxford University Press, amazon2013).Turing, Kasparov and the Future. ICGA Journal, Vol. 36, No. 1## Forum Posts

^{[15]}## External Links

^{[16]}^{[17]}^{[18]}## References

2004).The Essential Turing, Seminal Writings in Computing, Logic, Philosophy, Artificial Intelligence, and Artificial Life plus The Secrets of Enigma. Oxford University Press, amazon, google books2004).The Essential Turing, Seminal Writings in Computing, Logic, Philosophy, Artificial Intelligence, and Artificial Life plus The Secrets of Enigma. Oxford University Press, amazon, google books1953).. part of the collectionChessDigital Computers Applied to Games. in Bertram Vivian Bowden (editor),Faster Than Thought, a symposium on digital computing machines, reprinted 1988 in Computer Chess Compendium, reprinted 2004 in Chapter 16 of Alan Turing, Jack Copeland (editor) (2004).2004).2004).## What links here?

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