ABSTRACT
Aristotelian powers are part of the basic ontology of nature—at least as nature is pictured through the lens of modern science. Powers are the best way to make sense of familiar methods for inferring and testing causal claims in contemporary science, from physics to economics; and the use of what Pemberton has dubbed what-how-that evidence. Gravity does explain why heavy bodies fall and gravity is the power to make heavy bodies fall. Nomological machines produce the causal relations they do because of the way the exercisings of the various causal powers involved combine in the context of the machine to produce changes in the machine arrangement. Powers have canonical effects; indeed, their canonical effects are part of what it is to be that power. Each power produces its canonical effect, which is what is in the nature of that power to do. The powers ontology, the powers of things in their specific arrangements are there in the actual situation.
