Introduction

My title question as it stands is ambiguous, and is in want of some initial clarification. Does the question ask how the explanandum is logically related to the explanans? Or does it ask about the details of the dynamics of the explanation speech-act? Or does it ask how the linguistic ambiguities of explanation questions and answers should properly be unpacked? Or does it ask yet some other question?

The ways of studying explanation, like the ways of understanding the world, are many and varied. By this, I mean more than that the phenomenon of explanation can be studied as it arises in the different disciplines of biology, physics, the social sciences, and the like. Rather, I mean that there are varied disciplines of explanation-study itself. For example, the Hempelian tradition has largely focused on the logic of explanation, and others have focused on the linguistic, psychological, social, and epistemological angles of explanation. Thus, it is not appropriate for me to begin by arguing that explanation is a set of logically related statements or a speech-act (just as one does not begin by arguing ‘the world’ is a sociological or physical phenomenon), but appropriate instead to begin by specifying the explanatory discipline within which I ask my title question.

I ask my title question from within the epistemological discipline, the discipline addressed by Michael Friedman (1974), and more recently, by Philip Kitcher (1981). How do explanations—in whatever logical, linguistic, or social form—explain? Despite their differences, both Friedman and Kitcher argue that explanation explains by unifying. Moreover, they both see this unification in terms of some kind of numerical decrease.