The earliest chatterbot programs ever written say more about the human condition than they do about the nature of computer intelligence. The first, ELIZA -- or Dr. Eliza, as "she" was known -- had the persona of a Rogerian psychotherapist. Her successor, perhaps the inspiration for Marvin, the "paranoid android" of Douglas Adams' anarchic "The Hitchhiker's Guide to the Galaxy" novels, was named PARRY and was programmed to display the behavioral hallmarks of a paranoid schizophrenic.
ELIZA came into the world in 1966, at the Massachusetts Institute of Technology. Her father was a German professor named Joseph Weizenbaum, and at "birth" she was just 240 lines of programming code long.
Weizenbaum recognized that Alan Turing's "Imitation Game" test of computer intelligence required merely that the computer simulate intelligence, so he used some simple semantic tricks to create the desired effect. (It's no coincidence that his program shares the name of Eliza Doolittle, the erstwhile heroine of George Bernard Shaw's "Pygmalion," a flower girl trained up to act like a lady in a perfect example of an "imitation game.")