ABSTRACT
We will examine the positivist view of explanation in the form in which it has been presented and defended by Carl Hempel, since his account is, in several senses, exemplary.2 Let us begin with the following passage (1965a, p. 246), in which he describes a typical case of scientific explanation, and presents an analysis of it which indicates his general conception of such explanations:
Here, scientific explanation is presented as a form of logical argument. The conclusion of the argument is a statement describing the event which is to be explained-in this case, the behaviour of a mercury thermometer which is immersed in hot water. This statement is termed ‘the explanandum-statement’. The premisses of the argument are of two kinds: statements of general laws, and statements of antecedent conditions. These are termed ‘the explanans-statements’. Thus, schematically:
So far, we have talked of the ‘general conception of explanation’ presented by Hempel. But this phrase needs to be made more precise, and qualified in various ways, before we proceed to a further examination of his account. Hempel sees his task as that of providing the necessary and sufficient conditions for something to be properly regarded as a scientific explanation. That is, he wishes to specify certain conditions to which any scientific explanation must conform, and which are such that, if these conditions are satisfied, a legitimate explanation has been given. Such specifications are often termed a ‘model’ of scientific explanation. Hempel in fact offers more than one model, and these differ in some respects, whilst having several features in common. We can regard these as attempting to provide necessary and sufficient conditions for several, slightly different, types of scientific explanation.
