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1965
ELIZA
Joseph Weizenbaum (1923–2008)
ELIZA, named after the character Eliza Doolittle in the play Pygmalion by George Bernard Shaw, was the first program that could converse in English. It would take a line of text that a human being typed on a teleprinter, transform the text—for example, changing you to I and me to you—and then send back the text to the human typist. Just like a parrot, the computer had no idea what it was saying.
MIT professor Joseph Weizenbaum modeled his “language analysis program” on Rogerian psychotherapy, a type of nondirective therapy that does not involve interpretation of a client’s statements. Following this technique, ELIZA turned “I am unhappy” into “DO YOU THINK COMING HERE WILL HELP YOU NOT TO BE UNHAPPY?” Most of these transformations were triggered by simple keywords; when the program was stumped, it displayed a preprogrammed question.
Weizenbaum wasn’t prepared for what happened next. The program became immensely popular. People started conversing with the program as if it were intelligent—even people who knew better. Weizenbaum’s secretary, who knew that he had written the program, asked him to leave the room so that she could use the system without being watched. She was horrified when she discovered that Weizenbaum had logs of her interactions with the computer. A visitor to MIT who found it left running thought that he was using the teleprinter to talk to another professor—and then got angry when the “professor” answered his questions with other questions. Later, some people claimed that a computerized psychotherapist might be better in some cases than human ones—after all, they were always available and didn’t bill by the hour.
At its core, ELIZA knew nothing about the language that it used to communicate. In the final analysis, that lack of understanding didn’t matter.
“A large part of whatever elegance may be credited to ELIZA lies in the fact that ELIZA maintains the illusion of understanding with so little machinery,” Weizenbaum wrote in a 1966 article about the program. The power of the program was not its ability to understand what a person typed, but to conceal its lack of understanding.
SEE ALSO The Turing Test (1951), AI Medical Diagnosis (1975)
ELIZA was named after the character Eliza Doolittle, who was given speech lessons in George Bernard Shaw’s Pygmalion and later its musical adaptation, My Fair Lady. Here Eliza Doolittle is portrayed by Mrs. Patrick Campbell in 1914.