In theMetaphysics, Aristotle pointed out that some activities are engaged in for their own sake, while others are directed at some end. The test for distinguishing between them is to ask, ‘At any time during a period in which someone is Xing, is it also true that they have Xed?’ If both are true, the activity is being done for its own sake. If not, it is being done for the sake of some end other than itself. For example, if (...) I am thinking, it is true that I have thought. But if I’m making a blouse, it is not true that I have made a blouse, at least not this particular blouse. That’s not true until I have completed the project.There have been a number of attempts to deepen our understanding of this distinction. Anthony Kenny devoted a chapter of Action, Emotion, and Will to this issue, exploring the effect tense has on implication relations, and using that as a basis for dividing verbs of action into state-verbs, activity-verbs and performance-verbs. In more recent years the trend has been to generalize these categories so as to include occurrences other than actions, i.e., occurrences which do not involve intentions. While interest in this area tends to focus primarily on linguistic issues, such as the categorization of verbs, or on the logical analysis of sentences, there has been some interest in related metaphysical issues. In 1978 Alexander Mourelatos published ‘Events, Processes, and States,’ a paper which has turned out to be quite influential, in which he proposes an ontological trichotomy of occurrences. In his view, processes and events form distinct categories within the general category of occurrences. In this paper I will examine the reasoning underlying Mourelatos’s claim, arguing that the differences between processes and events cannot provide the basis for an ontological subcategorization of occurrences. (shrink)