States of mind as reasons for action

In chapter 1 I distinguished two very broad approaches to the philosophy of action: the inward-looking approach and the outwardlooking approach. According to the inward-looking approach we should look for the essence of agency in certain characteristic mental states, events or acts that accompany or cause physical behaviour. According to the outward-looking approach, we should look for the essence of agency in the acting agent's relationship with their environment: the adaptability of what they do to what they should do given the way the world is.

The idea, introduced in Chapter 2, that intentional action is essentially subject to justification is a way of putting some content into this second, outward-looking, approach. But this depends on justification itself being an outward thing not an inward thing. I have implicitly been assuming that it is: that behaviour is justified in virtue of its relationship with how the world is rather than being justified in virtue of its relationship with the agent's own mental states. So, in doing what you should do you are responding to the requirements of your environment rather than the requirements of your own psychology (although how you respond to the requirements of your environment is related to your psychology).

This assumption, however, can be questioned. The very opposite is simply taken for granted by many philosophers working on the nature of rationality and justification.