Nathan Salmón

Kripke’s examples of allegedly contingent a priori sentences include ‘Stick S is exactly one meter long’, where the reference of ‘meter’ is fixed by the description ‘the length of stick S’. In response to skepticism concerning apriority Kripke replaced the meter sentence with a more sophisticated variant, arguing that the modified example is more immune to such skepticism. The case for apriority is examined. A distinction is drawn between apriority and a broader notion, “qua-priority,” of a truth whose epistemic justification is dependent on no experience other than that required to justify belief of the deliverances of pure semantics. It is argued that Kripke’s examples are neither a priori nor qua-priori.

Metaphysics, Mathematics, and Meaning brings together Nathan Salmon's influential papers on topics in the metaphysics of existence, non-existence, and fiction; modality and its logic; strict identity, including personal identity; numbers and numerical quantifiers; the philosophical significance of Godel's Incompleteness theorems; and semantic content and designation. Including a previously unpublished essay and a helpful new introduction to orient the reader, the volume offers rich and varied sustenance for philosophers and logicians.

Paradoxes of nested modality, like Chisholm’s paradox, rely on S4 or something stronger as the propositional logic of metaphysical modality. Sarah-Jane Leslie’s objection to the resolution of Chisholm’s paradox by means of rejection of S4 modal logic is investigated. A modal notion of essence congenial to Leslie’s objection is clarified. An argument is presented in support of Leslie’s crucial but unsupported assertion that, on pain of inconsistency, an object’s essence is the same in every possible world. A fallacy in the argument is exposed. Alternative interpretations of Leslie’s objection are provided and are found to involve equivocation between different notions of “essence.” A material artifact’s modal essence, as distinct from its quiddity essence, could have been different than it is.

Four accounts, three of them Kantian, of true sentences of the form “ exists” are contrasted. Russell’s theory that such sentences are meaningless is contrasted with two other Kantian theories that are analogous to one another: Frege’s semantic-ascent theory and the Frege-inspired ungerade (indirect, “oblique”) theory. Frege’s objection to the semantic-ascent account of identity is applied, ironically with equal force, against his account of existence. A second argument favoring the ungerade theory is offered. The argument is then refuted through an application of a general strategy suggested by Kripke. A fourth theory, the deeply anti-Kantian existence-as-predicate theory, fully accommodates these results.