In 1900, in A Critical Exposition of the Philosophy of Leibniz, Russell made the following assertion: "That all sound philosophy should begin with an analysis of propositions is a truth too evident, perhaps, to demand a proof"¹ Forty years later, the interest aroused by this notion had not decreased. C. J. Ducasse wrote in the Journal of Philosophy: "There is perhaps no question more basic for the theory of knowledge than that of the nature of propositions and their relations to judgments, sentences, facts and inferences".² Today, the great number of publications on the subject is proof that it is still of interest. One of the problems raised by propositions, the problem of determining whether propositions, statements or sentences are the primary bearers of truth and falsity, is even in the eyes of Bar-Hillel, "one of the major items that the future philosophy of language will have to discuss".³