ABSTRACT
I want to consider another defense which I find most unsatisfactory. It might be called the positivist defense; and some philosophers seem to think it is the only defense available to someone who wants to claim that the apparent conflict between two theories is merely verbal. According to the positivist defense, whenever we have two theories that have all the same observational consequences, any apparent disagreements between the two theories are merely verbal ones. Call this the positivist principle.… For instance Sklar’s discussion of conventionalism about geometry seems to presuppose this view. In all the standard cases of alternate geometries (plus compensating adjustments elsewhere in the physical theories), the geometric objects of one theory are definable out of the geometric objects of the other. Sklar obscures this fact by comparing the conflict between alternative geometries to the conflict between the normal world-view and Descarte’s “evil demon” hypothesis; but this latter example is one where the objects of one theory are clearly not definable in terms of the objects of the other, so only by some form of the positivist principle could one claim that the conflict between those theories was purely verbal.
