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The Turing Test
Alan Turing (1912–1954)
““Can machines think?” That’s the question Alan Turing asked in his 1951 paper, “Computing Machinery and Intelligence.” Turing envisioned a day when computers would have as much storage and complexity as a human brain. When computers had so much storage, he reasoned, it should be possible to program such a wide range of facts and responses that a machine might appear to be intelligent. How, then, Turing asked, could a person know if a machine was truly intelligent, or merely presenting as such?
Turing’s solution was to devise a test of machine intelligence. The mark of intelligence, Turing argued, was not the ability to multiply large numbers or play chess, but to engage in a natural conversation with another intelligent being.
In Turing’s test, a human, playing the role of an interrogator, is able to communicate (in what we would now call a chat room) with two other entities: another human and a computer. The interrogator’s job is to distinguish the human from the computer; the computer’s goal is to convince the interrogator that it is a person, and that the other person is merely a simulation of intelligence. If a computer could pass such a test, Turing wrote, then there would be as much reason to assume that it was conscious as there would be to assume that any human was conscious. According to Turing, the easiest way to create a computer that could pass his test would be to build one that could learn and then teach it from “birth” as if it were a child.
In the years that followed, programs called chatbots, capable of conducting conversations, appeared to pass the test by fooling unsuspecting humans into thinking they were intelligent. The first of these, ELIZA, was invented in 1966 by MIT professor Joseph Weizenbaum (1923–2008). In one case, ELIZA was left running on a teletype, and a visitor to Weizenbaum’s office thought he was text-chatting with Weizenbaum at his home office, rather than with an artificial intelligence (AI) program. According to experts, however, ELIZA didn’t pass the Turing test because the visitor wasn’t told in advance that the “person” at the other end of the teleprinter might be a computer.
SEE ALSO ELIZA (1965), Computer Is World Chess Champion (1997), Computer Beats Master at Game of Go (2016)
“In the movie Blade Runner, starring Harrison Ford, the fictional Voight-Kampff test can distinguish a human from a “replicant” by measuring eye dilation during a stressful conversation.”