The Imitation Game

Instead of defining thinking, Turing proposed a game.

His original Imitation Game involved three people. A man and a woman answered typed questions from separate rooms. A questioner tried to work out who was who without seeing or hearing either person.

Then Turing changed one part: replace the man with a machine.

The hidden person and the hidden machine would both answer through typed messages. If the questioner could not reliably tell them apart, the machine would be succeeding at the game.

Turing did not give this idea one universal pass mark. He offered the game as a way to replace a vague argument about thinking with observable answers.

The test measures something visible from the outside: the answers. It does not measure what, if anything, the machine experiences inside.