Westinghouse sends a relay machine to play Nim with fairgoers

What happened

Nim is an old counting game. Players take turns removing objects from rows, and under the usual rules whoever takes the last one loses. It has a complete mathematical solution, which is exactly why it appealed to Condon. The machine his group assembled represented the rows as banks of light bulbs, let a visitor put lamps out by pressing buttons, and answered with a move worked out by telephone relays rather than by anything resembling programmable calculation. Nothing on the cabinet displayed a picture. The lights were the whole of it.

Westinghouse installed the machine in its pavilion as an advertisement for the company's own engineering, and across the fair's run it won the large majority of the games it played. The rare visitor who beat it took away a souvenir token. Condon, who went on to lead the National Bureau of Standards, described the design in a mathematics journal, and the group applied for a patent on a machine to play the game. It was a demonstration piece rather than a product, and when the exhibition closed the idea went with it.

The world at the time

The New York World's Fair sold visitors a mechanized future, with television receivers, a talking robot and model highways on display. Electronic computers did not yet exist in any practical form, and relay logic borrowed from telephone switching was the state of the art for automatic decision making. Games with tidy mathematical rules were the natural material for such a machine.

What it changed

The cabinet itself was dismantled and largely forgotten, but the pattern held. Nim-playing machines kept turning up at exhibitions on both sides of the Atlantic through the following decade. The argument the Westinghouse exhibit made on a fairground, that a machine could play a game well enough to beat you, became a standard measure of progress in computing.