The views of Quine and Strawson on the significance of 'mass terms' are rehearsed, and the metaphysical status of substances, in the chemist's sense, is considered. It is urged that the ontological dichotomy of particulars and universals is not adequate to accommodate such substances, which are in a sense to be explicated concrete but non-particular.

Definite descriptions, I shall argue, have two possible functions. 1] They are used to refer to what a speaker wishes to talk about, but they are also used quite differently. Moreover, a definite description occurring in one and the same sentence may, on different occasions of its use, function in either way. The failure to deal with this duality of function obscures the genuine referring use of definite descriptions. The best known theories of definite descriptions, those of Russell and Strawson, (...) I shall suggest, are both guilty of this. Before discussing this distinction in use, I will mention some features of these theories to which it is especially relevant. (shrink)