In interactive situations, agents can “learn” something that is not a preexisting truth. They can converge to an arbitrary convention, or tacit agreement. Once established they may even view it as an objective truth. Here we investigate accommodation dynamics for interpersonal comparisons of utility intervals. We show, for a large class of dynamics, convergence to a convention.

This article argues that there is a natural solution to carry out interpersonal comparisons of utility when the theory of gambles is supplemented with a group operation of joint receipts. If so, three types of people can exist, and the two types having multiplicative representations of joint receipt have, in contrast to most utility theories, absolute scales of utility. This makes possible, at least in principle, meaningful interpersonal comparisons of utility with desirable properties, thus resolving a long standing philosophical problem (...) and having potentially important implications in economics. Two behavioral criteria are given for the three classes of people. At this point the relative class sizes are unknown. (shrink)