This book comprises a study of the philosophy of language as contained in Michael Dummett’s semantics-based argument against metaphysical realism. This argument relies on two distinct theses, which underlie current philosophical thinking about language. One, whatever it is which determines the meaning of words and sentences must be manifested in the uses to which these items are put; that is, the determinants of meaning must lie open to public view. Two, metaphysical disputes can be reinterpreted as disputes about the type of meaning that should be assigned to statements. Primarily, statements whose truth value is beyond our capacity to know whether it obtains or not. The study will describe and elucidate the reductive character of these two theses, and will question their plausibility. The end result is a critique of Dummett’s semantic argument against realism.