This paper is intended to serve a twofold purpose. Its ultimate aim is the presentation of a syntactical definition of the degree of confirmation of a hypothesis on the basis of given evidence, a notion which is known to be of outstanding significance for the logic of inductive reasoning in the empirical sciences. The theory of confirmation to be developed here has as its foundation the theory of probability, and in order to make that foundation sufficiently secure, it was found expedient to present the theory of probability in axiomatic form and to introduce a syntactical interpretation of probability suitable for the intended application in the theory of confirmation. In this sense then to clarify the logical foundations of probability theory is this paper's first aim.