Abstract

In his philosophical works Wilfrid Sellars - like Ludwig Wittgenstein - clearly distinguishes the domain of philosophy from that of empirical sciences. Within the framework of this differentiation he insists on a further sharp distinction between the concepts of empirical or factual linguistics and those of pure semiotic. It is quite clear - thus Sellars's example - that formal logic and pure mathematics are not empirical sciences nor do they constitute branches of any such science. This distinction was historically gained from the development of pure syntax. According to Sellars, pure syntaxis concerned with „rules defining the formal structure of calculi rather than languages''. In a syntactic system understood in this sense we use neither the concepts of designation or truth, nor of verifiability or meaningfulness. The concepts used in logic and mathematics - taken as examples of such systems - are clarified through identification with concepts which occur in the formation and transformation of definitive rules of calculi. In this context, logic and mathematics are normative rather than factual sciences. The basis of their norms is grounded in humanly conceived rules.