The Semantic Turn: Tarski and Carnap

The research deals with the «semantic turn» of the 1930s in the work of two leading representatives of logical empiricism – Carnap and Tarski. The semantic turn was preceded by the «syntactic period», which has found expression in the «logical syntax of language» by Carnap and Tarski’s theory of logical consequence. The shift away from a purely syntactic interpretation of the language of science includes «Introduction to semantics» of Carnap and the model-theoretic conception of Tarski. It is shown that despite the proximity of semantic doctrines of both thinkers, the assumption about the impact of Tarski’s results on Carnap’s semantic research is not sufficiently substantiated. In particular, the central question of the possibility of a formal language of science – the question of the status of logical concepts or logical constants – was rather differently interpreted by Carnap and Tarski. Carnap was interested in the allocation of a class of analytic expressions in the language with the help of a well-defined class of logical constants, while Tarski doubted the whole idea of a fixed plurality of logical constants, believing that even purely set-theoretic concepts such as belonging to a set, if necessary, can be given the status of logical constants. Further, it is shown that the original motivation of Carnapian semantics was influenced by the philosophical doctrine of verification of the Vienna Circle, while the model-theoretic semantics by Tarski was aimed at solving logical mathematical problems.