Turing test, a procedure to test whether a computer is capable of humanlike thought. As proposed (1950) by the British mathematician Alan Turing, a person (the interrogator) sits with a teletype machine isolated from two correspondents—one is another person, one is a computer. By asking questions through the teletype and studying the responses, the interrogator tries to determine which correspondent is human and which is the computer. The computer is programmed to give deceptive answers, e.g., when asked to add two numbers together, the computer pauses slightly before giving the incorrect sum—to imitate what a human might do, the computer gives an incorrect answer slowly since the interrogator would expect the machine to give the correct answer quickly. If it proves impossible for the interrogator to discriminate between the human and the computer, the computer is credited with having passed the test.

Test proposed by Alan M. Turing to determine whether a computer can be said to “think.” Turing suggested the “imitation game,” wherein a remote human interrogator, within a fixed time frame, must distinguish between a computer and a human subject based on their replies to questions posed by the interrogator. A series of such tests would measure the computer's success at “thinking” by the probability of its being misidentified as the human subject. The test is performed today in competitions that test the success of artificial intelligence.

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