Joseph Weizenbaum

Joseph Weizenbaum bigraphy, stories - American artificial intelligence researcher

Joseph Weizenbaum : biography

8 January 1923 – 5 March 2008

Joseph Weizenbaum (8 January 1923 – 5 March 2008) was a German and American Computer scientist and a professor emeritus at MIT. The Weizenbaum Award is named after him.

Life and career

Born in Berlin, Germany to Jewish parents, he escaped Nazi Germany in January 1936, emigrating with his family to the United States. He started studying mathematics in 1941 in the U.S., but his studies were interrupted by the war, during which he served in the military. Weizenbaum returned to earn his M.S. in Mathematics.

Around 1952, Weizenbaum worked on analog computers, and helped create a digital computer for Wayne State University. In 1956 he worked for General Electric on ERMA, a computer system that introduced the use of the magnetically encoded fonts imprinted on the bottom border of checks, allowing automated check processing via Magnetic Ink Character Recognition (MICR). In 1964 he took a position at MIT.

In 1966, he published a comparatively simple program called ELIZA, named after the ingenue in George Bernard Shaw’s Pygmalion, which performed natural language processing. Driven by a script named DOCTOR, it was capable of engaging humans in a conversation which bore a striking resemblance to one with an empathic psychologist. Weizenbaum modeled its conversational style after Carl Rogers, who introduced the use of open-ended questions to encourage patients to communicate more effectively with therapists. The program applied pattern matching rules to statements to figure out its replies. (Programs like this are now called chatterbots.) It is considered the forerunner of thinking machines. Weizenbaum was shocked that his program was taken seriously by many users, who would open their hearts to it. He started to think philosophically about the implications of artificial intelligence and later became one of its leading critics.Miller, Stephen, MIT Professor’s Work Led Him to Preach the Evils of Computers, Wall Street Journal March 15–16, 2008, p. 6

His influential 1976 book Computer Power and Human Reason displays his ambivalence towards computer technology and lays out his case: while Artificial Intelligence may be possible, we should never allow computers to make important decisions because computers will always lack human qualities such as compassion and wisdom. Weizenbaum makes the crucial distinction between deciding and choosing. Deciding is a computational activity, something that can ultimately be programmed. Choice, however, is the product of judgment, not calculation. It is the capacity to choose that ultimately makes us human. Comprehensive human judgment is able to include non-mathematical factors, such as emotions. Judgment can compare apples and oranges, and can do so without quantifying each fruit type and then reductively quantifying each to factors necessary for comparison.

Weizenbaum was the creator of the SLIP programming language.

In 1996, Weizenbaum moved to Berlin and lived in the vicinity of his childhood neighborhood. Documentary film by Peter Haas and Silvia Holzinger. Wolfgang Löw, Leibniz-Institut für Neurobiologie, Magdeburg, Germany

A German documentary film on Weizenbaum was released in 2007 and later dubbed in English. The documentary film Plug & Pray on Weizenbaum and the ethics of artificial intelligence was released in 2010. Plug & Pray, Documentary film by Jens Schanze, featuring Joseph Weizenbaum, Raymond Kurzweil, Hiroshi Ishiguro

Until his death he was Chairman of the Scientific Council at the in Berlin. In addition to working at MIT, Weizenbaum held academic appointments at Harvard, Stanford, the University of Bremen, and other universities.

Weizenbaum was reportedly buried at the Jewish Cemetery in Berlin. A memorial service was held in Berlin on 18 March 2008.


  • "ELIZA — A Computer Program for the Study of Natural Language Communication between Man and Machine," Communications of the Association for Computing Machinery 9 (1966): 36-45.
  • Computer Power and Human Reason: From Judgment To Calculation, San Francisco: W. H. Freeman, 1976 ISBN 0-7167-0464-1