The question of whether the will is free, then, presupposes that the will is a substance, rather than a power, and therefore makes no more sense than the question of whether a man’s “Sleep be Swift, or his Vertue square” (E1–5 II.xxi.14: 240). To suppose that the will is free (or unfree!) is therefore to make a category mistake (see Ryle 1949: chapter 1).