Some of what Locke says suggests that he holds the “Doing” theory of action: “when [a Body] is set in motion it self, that Motion is rather a Passion, than an Action in it”, for “when the Ball obeys the stroke of a Billiard-stick, it is not any action of the Ball, but bare passion” (E1–5 II.xxi.4: 235—see also E4–5 II.xxi.72: 285–286). Here Locke is clearly working with a sense of “action” according to which actions are opposed to passions. But, on reflection, it is unlikely that this is what Locke means by “action” when he writes about voluntary/involuntary actions and freedom of action.  For Locke describes “a Man striking himself, or his Friend, by a Convulsive motion of his Arm, which it is not in his Power…to…forbear” as “acting” (E1–5 II.xxi.9: 238), and describes the convulsive leg motion caused by “that odd Disease called Chorea Sancti Viti [St. Vitus’s Dance]” as an “Action” (E1–5 II.xxi.11: 239). It would be a mistake to think of these convulsive motions as “doings”, for they are clearly things that “happen” to us in just the way that it happens to me that my arm rises when someone else raises it. Examples of convulsive actions also suggest that the Millian account of Locke’s theory of action is mistaken. For in the case of convulsive motion, there is no volition that one’s limbs move; indeed, if there is volition in such cases, it is usually a volition that one’s limbs not move. Such actions, then, cannot be composed of a volition and the motion that is willed, for the relevant volition is absent (more on volition below).