I want to ask ‘What kind of field is artificial intelligence?’ and to give an answer. Why is this an important question? Because there is evidence within AI of a methodological malaise, and part of the reason for this malaise is that there is not a generally agreed answer to the question.

As an illustration, several papers in this volume draw a number of different analogies between artificial intelligence and other fields. AI is compared to physics, to chemical engineering, to thermodynamics and to psychology; in fact it is said to be psychology. Each of these is a very different kind of field with different kinds of methodology, criteria for assessing research and so on. Depending on which of these you think artificial intelligence is really like, you would decide what to do, how to do it, and how to assess other people's work.

Evidence of malaise

One of the symptoms of this malaise is a difference amongst referees of papers as to the standard which is expected for conferences, journals, etc. When I was programme chairman of a major AI conference, I noted that for more than 50 percent of the papers the referees disagreed as to whether the papers should be accepted or rejected. And this wasn't just a question of having different thresholds of acceptability, because the opinions would reverse on other kinds of papers. So clearly the referees were applying very different criteria when deciding which papers were worth accepting.