John McCarthy receives the 1988 Kyoto Prize

The award

The Kyoto Prize is presented by the Inamori Foundation. In 1988 the prize in its Advanced Technology group went to John McCarthy, in the field of information science — designated at the time as the field of Computer Science and Engineering, Artificial Intelligence.^[1] The foundation's achievement digest carries a title that reads like a career summarised in one line: "Fundamental Contribution to the Field of Artificial Intelligence and the Invention of LISP, a Programming Language".^[1]

The laureate

The biographical note in the citation is short. John McCarthy was born in Boston in 1927 and was admitted to the California Institute of Technology at the age of 16.^[1] Almost all the rest of the digest is about the work. It calls him "the Father of Artificial Intelligence," and it describes LISP as being considered the greatest invention of the century in the field of computer science.^[1]

Two achievements, one award

The pairing is the substance of the award: a field and a language, named together. Artificial intelligence is the project of getting machines to do things that would require intelligence if a person did them — recognising a face, planning a route, answering a question, drawing a conclusion. LISP is a programming language designed for that kind of work rather than for numerical calculation. It operates on symbols and lists; its programs are written in the same structures as its data, so a program can be handled like any other object — taken apart, rebuilt, passed to another program. That shape lets a programmer write rules and procedures down as data, which is convenient when the rules themselves are the thing being studied.

Common sense reasoning

The first achievement the citation names is McCarthy's study "Common Sense Reasoning," which attempted to formalize a logic of inference on common sense in order to endow computers with reasoning ability comparable to that of human beings.^[1] The words matter. A logic of inference is a set of rules for deriving new statements from old ones; to formalize it is to write those rules in a precise notation, with no step left to intuition, so that a machine can apply them and a reader can check them. Common sense is the hardest possible target for such a treatment, because it is exactly the knowledge people never write down: that a released cup falls, that a room stays where it is after you leave it, that one object cannot be in two places at once. Making that knowledge explicit, in a form a program can use, turned out to be far harder than making a program good at a narrow, well-defined task — and it remains one of the central problems of the field.

The commemorative lecture

On 11 November 1988 McCarthy delivered the commemorative lecture "The Logic and Philosophy of Artificial Intelligence" at the Kyoto International Conference Center.^[1] The title joins two words that are usually kept apart. Logic supplies the formal languages in which rules of inference can be stated exactly; philosophy asks what knowledge, meaning and mind are, and therefore what it would mean for a machine to have any of them. A lecture that promises both is a lecture about foundations rather than about any particular program.

What such an award records

A prize is a record as much as a reward. The 1988 digest puts a person, a field and a programming language into the same sentence, and states plainly which parts of the work the committee thought the field rested on: an attempt to formalize common-sense reasoning on one side, a language for writing programs on the other.^[1] Readers who come to the subject later can use that sentence to see how the field described itself at the time — not only what had been built, but what was counted as fundamental.