An Introduction to the Philosophy of Science

Introduction

That we use scientific theories to explain things is a matter of broad (though incomplete) agreement. But what is it to explain something? Intuitively, explanations enable us to understand the phenomena we observe, where understanding involves something more than merely knowing that something occurs. Intuitively, again, that something more seems to involve a knowing why or knowing how the phenomenon occurs. But none of these intuitive ideas helps very much with an analysis of what constitutes an explanation (or what constitutes a good explanation). For what constitutes understanding? and what does it take for an explanation to help us achieve it?

This is a very old question in philosophy. Aristotle insisted that in order to “grasp the ‘why’ of something” one should understand each of its four different kinds of cause: what it is made of, its form, its source of change or stability, and its end or purpose.

Aristotle's four causes are really four kinds of explanation, and they reflect his own approach to explaining natural phenomena. The discussion of explanation within contemporary philosophy of science likewise draws motivation from the explanatory practices of contemporary science; it really begins with Carl Hempel and Paul Oppenheim's Deductive-Nomological (D-N) model of explanation, which constitutes the core of the Covering Law model. We will therefore begin with the Covering Law account and objections to it before turning to several prominent alternative accounts.