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# Responsiveness

Requiring that answers to questions be responsive as well as truthful raises questions involving intentionality and/or metamathematics.

Suppose I ask someone at a party, ``Who is that man over there?'' and he replies ``Tom Jones''. That would normally be considered a responsive answer. Suppose that instead I ask, ``Who is Tom Jones?'' and the replies, ``That man over there''. This is also normally considered responsive. This indicates that the general problem of responsiveness is difficult, and we shall want to consider some special cases.

Stating and proving that answers to questions and other statements are responsive seems to require a substantially larger logical apparatus than merely proving that the answers are truthful. It turns out that the logical apparatus proposed in (McCarthy 1979b), which uses separate notations to denote objects and concepts of objects is suitable for the task.

An answer is responsive provided the questioner will know the answer to the question after he receives it. Suppose Pat asks for Mike's telephone number. An answer like ``Mike's telephone number is the same as Mike's wife's husband's telephone number'' is unresponsive, and can be characterized as by noting that it doesn't make Pat know Mike's telephone number. Using (McCarthy 1979b) we can define

Here the function Concept1 maps a telephone number into a standard concept of that telephone number, i.e. one that permits the person who has it to dial the number. The range of Concept1 needs to be suitably axiomatized.

John McCarthy
Fri Nov 6 21:37:30 PST 1998