Ceteris Paribus Laws

Abstract

A strict law of nature might tell us that F events always cause G events, or that every F event has such-and-such objective chance of causing a G event. A ceteris pasribus law, if there are any, might tell us that F events cause G events ceteris pariibus, or, to confine expression to a single language, that F events cause G events all other things being equal. Some philosophers believe that there are ceteris paribus laws and that without them there would be no special-science explanations, and hence no special sciences. These philosophers think that science is in the business of providing scientific explanations, that such explanations require laws, and that there are no, or only very few, strict special-science laws; whence their appeal to ceteris paribus laws. I say 'these philosophers', and I know there are many, but I particularly have in mind a colleague who is especially fond of ceteris paribus laws, and especially concerned to stress their importance in commonsense psychology and in those departments of cognitive psychology that are refinements of the folk theory. Jerry Fodor wants to account for the causal-explanatory role of psychological properties, and he thinks that to do this those properties must occur in psychological laws. At the same time, he recognizes that those laws aren't strict, in that they don't have completions in the language of psychology. But that's OK, he says, because they are correct ceteris paribus laws, which is all that's needed. In this respect, he further says, psychology, both commonsense and scientific, is in the same boat as any other special science. He even goes so far as to say that