All Kinds of Possibility

Q NE reads of many kinds of possibility: physical, logical, epistemic, de dicto, de re, technical, theoretical, economic, human, real, metaphysical. I describe a simple grammatical device that helps put these cross-cutting classifications in their places. The proposed framework has consequences for essentialism, the ontology of possible things, the number of planets, possible worlds, rigid designators, and the philosophy of Leibniz. For example, in English there are a number of distinct grammatical derivations of expressions of the form, possible-so-and-so. Ignoring the distinctions, Quine launched a notable attack on possible things, and thereby on essentialism and modality. This prong of his attack fails when directed at any of the possible so-and-sos that are grammatically admissible, for none of them can offend even the most intransigent nominalist. But I contend that the philosophers' possible world either cuts across a grammatical distinction or gains sense through a cosmology such as that of Leibniz. So the admissibility of the possible-so-and-so construction, although contrary to Quine, is of no solace to today's possible-world semanticist. For another example, we find in our grammar a counterpart to the disputed contrast between de re and de dicto. The neatness of the grammatical distinction shows that the philosophical one is viable. Indeed, grammar terminates some controversy, because the de re possibility that it defines is referentially transparent, and the problems of opacity for de dicto constructions turn out to have nothing to do with modality. But the basis of the grammatical distinction is incompatible with the drift toward essentialism so often noted in the exponents of modal logic. Naturally this result does not preclude essentialism as a philosophical theory, any more than the preceding paragraph stops us from inventing non-Leibnizian possible worlds. But it does debar the essentialist from appealing to "intuitions" of "ordinary linguistic behavior" because what he is trying to construct cuts