Inventing ELIZA is the first full critical study of Joseph Weizenbaum’s 1966 chatbot, and its centerpiece is primary evidence: the rediscovered original source code plus scripts missing for decades, drawn from archives at MIT, Stanford, and UCLA. Assembled by a team of scholars for MIT Press, it argues the program dismissed for years as a “simple pattern-matcher” was a far more inventive system than the myth allows. A rare chance to read the actual code behind the machine that started the “is it really thinking” argument.