Theoretical Realism and Theoretical Equivalence

Abstract

The true correlate of sensibility is not known and cannot be known…-KANTA great many philosophers have thought it impossible that there should exist two distinct theories between which no possible evidence could discriminate. This doctrine, and more rarely its denial, have often been the cynosure of dogmas and disputes about conventions within physical theory, about simplicity, about measurement in quantum mechanics, and most recently, about radical translation. The list is long enough to make it important to know whether or not the doctrine is true. I shall argue that it is, indeed, not true.The thesis that empirically equivalent theories are synonymous was central to Hans Reichenbach's philosophy of science, and especially to his notion of ‘equivalent descriptions’ and to his account of simplicity:There are cases in which the simplicity of a theory is nothing but a matter of taste or of economy.