There is a well-known model of rational agency according to which a rational person’s reasons for doing X will be such that doing X is either his end, or is something he takes to be a means to his end (or one of his ends). According to this model, a person has as end or goal some achievable state of affairs, such as feeling pleasure, and this goal renders certain courses of action prima facie suitable, namely those courses which would bring about the state of affairs, or would raise the likelihood of its coming to be. The person may have false beliefs about which courses of action are thus suitable for him, but this merely indicates the need for a distinction, between what he has ‘objective’ reason to do, and what he has ‘subjective’ reason to do. His practical rationality will not as such be impugned if he does something which is only ‘subjectively’ rational, though his theoretical rationality may be impugned, if it is the explanation for why the relevant belief of his is false.

This sketch will be familiar, as describing a model of rational choice which is standard among economists and decision theorists, its key notion being that of ‘expected value’, or alternatively ‘expected utility’. It is a sketch only, and more detail could be added. But for present purposes, we need only look at a class of reasons for action which are inexplicable on this model of agency – namely, backward-looking reasons.

An example of a backward-looking motive is the motive of gratitude for a service done. As Elizabeth Anscombe brought out so effectively, reasons and motives are alike elicited by the question ‘Why?’, as in ‘Why are you doing that?’, and if I ask you why you are sending flowers to Emily, let us suppose you reply, ‘Because she drove me to hospital when I broke my arm.’ On the face of it, your reason mentions a past fact, a fact of recent history. But the philosopher who adheres to the ‘expected utility’ model will look for a way of describing your action that makes it appear to be aiming at bringing something about, and will thus reject ‘Because she drove me to hospital’ as a statement of the ‘real’ reason.