Despite the fact that Aristotle and Frege/Russell differ in how to understand the ambiguity in the meaning of the word “is”, their theories share a common feature: “is” does not have a normative meaning, but a constative meaning. This paper, however, shows (1) that there is a normative meaning of “is” (and correspondingly a constative meaning of the word “ought”) and (2) that the ambiguity of “is” is itself ambiguous. Furthermore, the paper proposes (3) a performative criterion for making a distinction between constative and normative “is”. It is thereby possible to attack Searle’s famous argument against Hume’s law.
Cf. for the fallacy in Searle’s argument against "Hume’s law" also Ferber, Rafael (1994). Moral Judgments as Descriptions of Institutional Facts. In: Meggle, Georg; Wessels, Ulla: Analyomen 1, Proceedings of the 1st Conference "Perspectives in Analytical Philosophy". Berlin: Walter de Gruyter, 719-729, esp. 722-724: