What constitutes an agent? I believe that we — that is, we rational beings — constitute ourselves as agents, by choosing our actions in accordance with the principles of practical reason, especially moral principles.1 It sounds paradoxical, I know. How can we constitute ourselves, or choose our actions one way or another, unless we are already agents? How can we take control of our movements, unless we are already in control of them?
In [these essays], I try to think about agency, rationality, and virtue, in the company of Plato, Aristotle, Kant, and Hume, in effect asking them what they think about these issues, and trying to work with the answers that they give.
In the philosophical tradition, Reason...refers to the active rather than the passive or receptive aspect of the mind. Reason in this sense is opposed to perception, sensation, and perhaps emotion, which are forms of, or at least involve, passivity or receptivity.
Any conscious animal is guided through her environment by means of her perceptions and her desires or instinctive impulses. Her perceptions constitute her representation of her environment and her desires and instinctive impulses tell her what to do in response to what she finds there. ...Either through original instinct or as a result of learning, an animal represents the world to herself as a world that is, as we might put it, already normatively interpreted, in the sense that she perceives things in terms of her own interests. ... Exactly how any given kind of animal’s representations give rise to his or her actions is a matter to be investigated empirically. But however it may be with the other animals, there is no question that we human beings are aware, not only that we perceive or desire or fear certain things, but also that we are inclined to believe and to act in certain ways on the basis of these perceptions or desires or fears. We are aware not only of our representations and desires as such but also of the way in which they tend to operate on us. That is what I mean by saying that we are aware of the potential grounds of our beliefs and actions as potential grounds. And this awareness is the source of Reason. For once we are aware that we are inclined to believe on the ground of a certain perception, or to act on the ground of a certain desire, we find ourselves faced with a decision, namely, whether we should do that — whether we should draw the conclusion, or perform the action, on the ground in question, or not.
Once the space of awareness—of reflective distance, as I like to call it—opens up between the potential ground of a belief and the belief itself, or between the potential ground of an action and the action itself, we must step across that distance with some awareness that we are doing so, and so must be able to endorse the operation of that ground as the basis for what we believe or do. And a ground of belief or action whose operation on us as a ground is one that we can endorse is a reason. This means that the space of reflective distance presents us with both the possibility and the necessity of exerting a kind of control over our beliefs and actions that the other animals probably do not have. We are active, self-directing, with respect to our beliefs and actions to a greater extent than they are. And it is the same fact that we now both can have, and absolutely require, reasons to believe and act as we do.