Aristotle marks this distinction between the way I was moving and the way the wolf moves by inventing a word: "energeia" which he constructs from the perfectly normal noun "ergon" meaning work or task and to which he adds the prefix "en" which suggests an undertaking and a suffix which suggests activity. Energeia (that's right, it sounds like our word energy) was a word Aristotle had to invent in order to capture a certain defining feature of the sort of being that we are, a feature of the being who is human that philosophers since Aristotle have failed, for the most part, to comprehend. My plan for this essay is to investigate that peculiar feature of the human being by thinking about the difference between what I was doing as I drove across the Park that week in mid-February and what it is that the wolves who laid down some of those tracks were doing as they moved across the land.