The Assumptions — Imperfect Knowledge, Divided Expectations and the Discount

Abstract

Certain assumptions underlie our treatment which should be made explicit, for they determine the limitations and scope of the theory. We have already pointed out the limitation that the theory is only intended to apply to a single act of choice of the individual. But to some extend this restriction on the applicability of the theory is only apparent, for at a later stage in the argument we show that the theory covering a single act of choice of the individual covers also the case in which the objects of choice are complementary. The individual’s choice on the topic b is linked up with his choice on the topic a; or in which his choices, taken in that time order, on the topics a, b, c, ... are interdependent. Since virtually all of a person’s choices are in fact interdependent in this way, each depending on choices which have already been taken and on others the individual expects to take, an account of complementarity greatly extends the range of choices to which the theory is applicable.

In this paper, Black expands the notion of complementarity to argue that the theory covering a single act of choice of the individual is more applicable than accepted by theorists. He argues that it covers also the case in which the objects of choice are complementary and that the individual’s choice on the topic b is linked to his choice on the topic a; or in which his choices, taken in that time order, on the topics a, b, c,.. n are interdependent. Black argues that all personal choices exhibit the potential for interdependence in this way with each depending on choices which have already been taken and on others the individual expects to take. Black’s view of complementarity greatly extends the range of choices to which the theory is applicable. To Black the absence of knowledge about one’s own desires, the general course of events, the consequences of one’s own choices, and even the absence of definite expectations, does not restrict the applicability of his theoretical construct. The only requirement for the theory to apply is that it should be legitimate to draw the schedules of desire.