What is an action?

In this final chapter I want to explore the metaphysics of action. By metaphysics I do not mean anything unworldly or unobservable. The question at issue here is what sort of thing an action is if it is a thing at all. Can we identify actions with things that we have a better understanding of? Are actions identical with body movements? Or are they identical with sequences of things starting inside the agent's mind with their intentions, going through their body movements and finishing with external results being achieved? We can also ask about the spatial and temporal extent or duration of actions. Where and when are they? Do they extend beyond the body of the agent into the world around them? Do they continue after the agent stops moving or do they even continue until the agent starts moving?

In Chapter 5 I raised the possibility that actions are not events at all. Your action – the thing you do – is the sort of thing that is justified, not caused; whereas the process of acting in a certain way or the event of that process happening is the sort of thing that is caused, not justified. This suggests that what is justified – your action – might not have any particular identity; it might not even be an identifiable particular. And then it would be inappropriate to ask the metaphysical questions I have just raised about its identity.