In a recent paper Lawrence Davis has argued that the difference between an arm raising and someone raising his arm is that in the latter case a volition causes the arm to rise. In this paper I will show that Davis's theory is faulty and that certain obvious ways of repairing his theory do not work.

Davis proposes the following as an account of Sam's raising his arm:

According to Davis the volition — Sam's willing to raise his arm — need not be interpreted psychologically. Volitions could be ghostly mental events, but they might not be. He leaves this open. He also leaves open the question of whether volitions are introspectable events. Davis allows that in some cases Sam's arm rising can be caused by a volition different from the volition to raise his arm. For example, Sam might will to step on a pedal.