Philosophers and scientists agree that an important characteristic of theories is their internal coherence. I propose that there is a particular type of internal coherence, termed “unit coherence,” that has received insufficient attention from psychologists. When psychologists theorize about the mechanisms that bring about human behavior, the units in which the variables are expressed need to be consistent throughout the theory; this is unit coherence. The theory of reasoned action is an example of a unit incoherent theory. I explain why (...) this is so and also show how the theory can be made to be unit coherent. I also include examples of unit coherent theories to demonstrate that they are possible to have in psychology. Although the concept of unit coherence is somewhat subtle, it has surprising and far-reaching consequences. (shrink)

The debate over whether we should believe that mathematical objects exist quickly leads to the question of how to determine what we should believe. Indispensabilists claim that we should believe in the existence of mathematical objects because of their ineliminable roles in scientific theory. Eleatics argue that only objects with causal properties exist. Mark Colyvan’s recent defenses of Quine’s indispensability argument against some contemporary eleatics attempt to provide reasons to favor the indispensabilist’s criterion. I show that Colyvan’s argument is not (...) decisive against the eleatic and sketch a way to capture the important intuitions behind both views. (shrink)

On the received view, the Representational Theory of Measurement reduces measurement to the numerical representation of empirical relations. This account of measurement has been widely criticized. In this article, I provide a new interpretation of the Representational Theory of Measurement that sidesteps these debates. I propose to view the Representational Theory of Measurement as a library of theorems that investigate the numerical representability of qualitative relations. Such theorems are useful tools for concept formation that, in turn, is one crucial aspect (...) of measurement for a broad range of cases in linguistics, rational choice, metaphysics, and the social sciences. (shrink)