 The concept of a unique successor to every number might be a defining feature of the lexical item, “number,” but that doesn’t itself imply that an infinity of numbers actually exists. Meanings and concepts are one thing; reality quite another. Justification of such existential statements and, with them, Hume’s Principle would seem to have to involve something more than appealing to merely the concept, but also —to recall Quine’s (CLT, p. 121, §3.3 above) claim— to “the elegance and convenience which the hypothesis brings to the containing bodies of laws and data,” i.e., to our best overall empirical theory of the world, irrespective of what constraints language might impose (see Wright, 1999, and Horwich, 2000, for further discussion).