Joseph Weizenbaum (8 January 1923 - 5 March 2008) was a German-American mathematician and computer scientist. He was born in Berlin. He became famous for writing the program ELIZA, which simulated a doctor, in the 1960s. He also became well-known for having a critical attitude to what computers can and should do. Weizenbaum died of a stroke at age 85, in 2008.