The first meeting on artificial intelligence did not go all that well. In summer 1956, on the back of early successes in computer design, leading lights of the new science of information theory met at Dartmouth College in New Hampshire to thrash out a plan for emulating the thought processes of the human mind. The organisers thought it would just take a summer school to formulate a coherent programme of research to ultimately create a human-level intelligence.

According to John McCarthy, then a mathematical professor at the college and an organiser of the event, people drifted in and out of the summer meetings and the group could not agree on how they would proceed. Some backed the idea of emulating neurons in the brain; others thought intelligence could be achieved using symbolic maths. Despite the splits, there was plenty of confidence.

By the 1970s, the early enthusiasm was dissipating. A survey of 70 computer scientists working in AI-related fields...