1.Following Kripke, many philosophers have accepted the existence of propositions concerning essences, and, more generally, propositions asserting necessities, that are knowable only a posteriori. Such an acceptance is consistent with the claim that ultimately all knowledge of necessity is a priori. A posteriori knowledge of necessity may be held to be a consequence of the combination of a priori knowledge of a proposition asserting essence or necessity with a posteriori knowledge of a non-modal proposition. E. J. Lowe (2007: 287–88) denies (...) even this kind of derived a posteriori knowledge of essence or necessity. He reconstructs the form of an argument that is intended to lead to a proposition concerning essence but which is known a posteriori: This schema may be exemplified thus: As this example illustrates, instances of (1) are a priori propositions concerning essence, while instances of (2) are a posteriori propositions; instances of the conclusion are propositions asserting particular essences, and are, it is claimed, knowable only a posteriori.1. (shrink)