The promise

Expectations ran ahead of results twice. In 1973 Sir James Lighthill's report for the British Science Research Council found that the field had not delivered on its promises, and funding in the United Kingdom fell away. In the 1980s expert systems revived the money: Digital Equipment's XCON configured computer orders with thousands of rules, and Japan's Fifth Generation project (1982) set out to build machines that reasoned. Companies were founded to sell hardware for the Lisp language. By 1987 that market had collapsed, and the phrase "AI winter" had been coined at a 1984 conference by people who saw it coming. Investment and progress did not move together. While budgets fell, small groups kept working: backpropagation for training multilayer networks was published in 1986, Yann LeCun's convolutional network read handwritten digits by 1989, and Gerald Tesauro's TD-Gammon learned backgammon from self-play in 1992. The quiet work was done in the cold.