This chapter narrows the field of enquiry to that of semantics, i.e., it will be concerned with signs and their representational functions. Once again a change with respect to epistemologically oriented post-cartesian philosophy must be noted: an important achievement of contemporary philosophy has been its elimination of psychologism, of the confusion of subjective and objective concepts. Indeed, many philosophers reacted so strongly against psychologism that they not only relegated subjective concepts from the sphere of logic to that of psychology, but also abandoned objective concepts (Frege's sense) and restricted themselves to the two-level semantics of linguistic signs and represented reality. Thus, as we shall see, Russell's theory of descriptions put forward the view that it is unnecessary to assume, in addition to the reference, a special level for the sense of the words. (His theory, incidentally, will also serve as example for a third kind of logistic analysis.) And Leśniewski's disciple, Tarski, whose system is the first strictly formulated and non-contradictory semantical system, also proposes a two-leveled correspondence theory of truth, where not the concepts, but the graphical signs are correlated with reality.