Turochamp by Alan Turing and David Champernowne from 1948 is the first computer game ever written. It is a chess simulation that was developed as a chess playing algorithm and implemented as a „paper machine“, since unfortunately it was never implemented on a computer. Since there was not yet a machine that could execute instructions, Turing acted as a human CPU that took more than half an hour per move. Turing says that the rule system set forth in „Chess“ is based on an „introspective analysis“ of his own thought process while playing (albeit 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 countermoves; the use of evaluation rules that assign numerical values to board configurations that indicate strength or weakness; the minimax strategy; and variable foresight, in which, rather than tracking the consequences of each possible move equally far, the „more profitable moves are considered in more detail than the less profitable ones.“ Turing also recognized the need to use „an entirely different system for the endgame.“ In his 1953 paper „Chess,“ Turing defines evaluation characteristics and discusses minimax strategy, variable foresight, rest, and even learning as early examples of a genetic algorithm. He does not specifically mention the name Turochamp, but the „machine“ and its play against a human.
