Abstract

Section 2 will begin by formulating Reichenbach’s principle of common cause in a more general way than is usual but in a way that makes the idea behind it a lot clearer. The way that Salmon has pushed the principle into the services of scientific realism will be explained in terms of an example, van Fraassen objects, Salmon modifies his stand and van Fraassen rejoins - all in section 2. (See van Fraassen 1980, chapter 2).In this episode I think van Fraassen right in claiming - against Salmon that there is no categorical imperative for common cause explanation, and I add my own examples in section 3. The first example ‘is the explanation of the correlation between the equilibrium positions of two objects on a balance in terms of their property of “mass” and the law of moments.