First, I establish on the basis of a few texts in the Timaeus the need for this type of semantic interpretation. These passages occur in three clearly identifiable contexts, each concerning how best to think and talk about various aspects of the universe. The first passage constitutes one of two premises in the argument concerning the relation between time and eternity; the second involves an analogy pertaining to the Receptacle; the third clarifies the language for spatial directions that can obtain (...) in a spherical universe. Having thus shown that this sense of the language is indeed present in this dialogue, there follows an extended application to and discussion of three passages in which this language is also prominent, the first of which has commanded significantly more scholarly commentary than have the other two: (1) the other premise as well as the conclusion of the argument about the relation between time and eternity, (2) the analogy between the four primary natural bodies and the letters of a language, and (3) for the second time, the number of worlds that exist. The paper concludes with an argument against Vlastos’ notorious claim that Plato here amounted to a scientific Luddite who set Greek science back by crushing fact with value; Plato is, on the contrary, merely indicating the epistemological dependence of the whole of empirical science upon metaphysics. (shrink)