Within the category of actions, Locke distinguishes between those that are voluntary and those that are involuntary. To understand this distinction, we need to understand Locke’s account of the will and his account of willing (or volition). For Locke, the will is a power (ability, faculty—see E1–5 II.xxi.20: 244) possessed by a person (or by that person’s mind). Locke explains how we come by the idea of power (in Humean vein, as the result of observation of constant conjunctions—“like Changes [being] made, in the same things, by like Agents, and by the like ways” (E1–5 II.xxi.1: 233)), but does not offer a theory of the nature of power. What we are told is that “Powers are Relations” (E1–5 II.xxi.19: 243), relations “to Action or Change” (E1–5 II.xxi.3: 234), and that powers are either active (powers to make changes) or passive (powers to receive changes) (E1–5 II.xxi.2: 234). In this sense, the will is an active relation to actions.