Abstract
Action theory has given rise to some perplexing puzzles in the past half century. The most prominent one can be summarized as follows: What distinguishes intentional from unintentional acts? Thanks to the ingenuity of philosophers and their thought experiments, we know better than to assume that the difference lies in the mere presence of an intention, or in its causal efficacy in generating the action. The intention might be present and may also cause the intended behavior, yet the behavior may not be an intentional action; it may not be an action at all. The classic example is that of the nervous nephew who intends to kill his uncle to inherit his estate, and whose intention makes him so nervous as to drive recklessly, thereby running over a pedestrian... who happens to be his very uncle. The intention to kill is present and it causes the killing, yet the killing is not an intentional action. Rather, what appears to distinguish intentional from non-intentional action is voluntary control of the proper sort, and what distinguishes action from non-action is behavior caused in a particular manner. But spelling out the sort and specifying the manner have proven vexing tasks.