Interrogative Logic and the Economic Theory of Information

It is with great pleasure that I return to earlier work based directly (Dacey 1979b) and indirectly (Dacey 1979a, 1981a, 1981b, 1985) on the fruits of Jaakko Hintikka’s labors. In particular, it is a great pleasure to work in the area of Hintikka’s interrogative logic, which provides a systematic approach to the many subfields of philosophy (Hintikka 1968/1999, 1973, 1974, 1975, 1976, 1985, 1993; Hintikka and Hintikka 1989; Hintikka, Halonen, and Mutanen forthcoming/1999; Hintikka and Kulas 1983). One open area within interrogative logic pertains to situations where the inquirer receives “merely probable answers [from] Nature” (Hintikka 1988/1999, p. 156). One approach to this open area is the economic theory of information as advanced by Jacob Marschak (1971, 1974). Indeed, Marschak shows that the economic theory of information can be employed within the context of Hintikka’s general interrogative logic to account for probable answers as they appear in both pragmatic (i.e., economic) and inductive (i.e., epistemic) decision making (Marschak 1974, particularly pp. 145-149 and pp. 167- 169).