Alex Gregory

What is it to want something? Or, as philosophers might ask, what is a desire? The book defends “desire-as-belief”, the view that desires are just a special subset of our beliefs: normative beliefs. This view entitles us to accept orthodox models of human motivation and rationality that explain those things with reference to desire, but nonetheless to make room for our normative beliefs to play a role in those domains. And this view tells us to diverge from the orthodox view on which desires themselves can never be right or wrong. Rather, according to desire-as-belief, our desires can themselves be assessed for their accuracy, and they are wrong when they misrepresent normative features of the world. Hume says that it is not contrary to reason to prefer the destruction of the whole world to the scratching of your finger, but he is wrong: it is foolish to prefer the destruction of the whole world to the scratching of your finger, and this is foolish because this preference misrepresents the relative worth of these things. The book mounts a defence of these ideas.

This chapter describes the version of desire-as-belief that I defend. Roughly, I say that just as "disbelieves P" is shorthand for "believes not-P", "desires P" is shorthand for "believes has reason to bring about P". I explain how this view is consistent with the opposing "directions of fit" of belief and desire, and mention some broad attractions of the view and general strategies for defending it. Along the way, I explain how the view permits that it is rational to have conflicting desires.

This chapter and the next combine to provide an argument for desire-as-belief. But this chapter itself just focuses on more general questions about desire and motivation. I defend "ODM", the view that only desires can motivate us. This view is a part of the Humean orthodoxy, and a part that I accept. The chapter argues for ODM and defends it from various objections.

You might believe that you ought to exercise or that Sarah has some reason to eat more porridge. I argue that such normative beliefs have a special connection with motivation, though this connection has often misdescribed and so this kind of "judgement internalism" thereby underestimated. I then combine thoughts about this connection with the claims in the previous chapter, in order to generate an argument that seems to favour either non-cognitivism or else desire-as-belief. The remainder of the chapter explains why the argument really counts in favour of desire-as-belief, and against non-cognitivism. The basic concern is that non-cognitivism makes poor sense of our normative beliefs about other people.

This chapter develops a second argument for desire-as-belief. It is rational to respond to your desires. Why is this true? Standard dispositional accounts of desire fail to explain why. But desire-as-belief can, by appeal to a widely accepted enkratic principle, according to which it is rational to respond to your own normative beliefs. The chapter goes on to explain how this reasoning strongly favours desire-as-belief over "presentationalism", a recent rival view on which desires are more akin to perceptual states than beliefs.

A classic objection to desire-as-belief appeals to irrationality in desire. It might seem that we can believe we have reason to do things but without desiring to do them (perhaps: giving money to charity), and that we can desire to do things without believing we have reason to do them (perhaps: eating yet another slice of cake). This chapter responds to many such objections, especially worries about desire-as-belief and akrasia.

This chapter first contrasts desire-as-belief with the "besire" theory, arguing that the former is superior. It then discusses possible ways in which desires might be constrained by our normative beliefs. Desire-as-belief commits us to one such constraint: that you can only desire something if you believe you have reason to bring it about. I argue that this constraint is plausible, and more plausible than the idea that you can only desire something if you believe it good. Distinguishing these claims also allows us to see that desire-as-belief permits various kinds of divergence between our desires and *some* of our normative beliefs. Along the way, the chapter also discusses some related questions about variation in desire between people, and the distinction between wanting, wishing, and hoping.

This chapter discusses the ways in which our desires relate to different kinds of feelings, such as emotions, appetites, and pleasure. I explain how desire-as-belief can accommodate those connections. I argue that emotions dispose us to form certain normative beliefs, and this explains their influence on desire. Both appetites and likings should be distinguished from desires, though they often give rise to desire; I explain how desire-as-belief predicts such facts, and explain how these distinctions allow desire-as-belief to avoid some objections.

This chapter discusses two topics. First, an objection to desire-as-belief that appeals to mismatches between degrees of belief and degrees of desire. The essential problem is that we can be uncertain in our beliefs, but it is not clear that there is any equivalent feature of our desires. After discussing various bad solutions to this puzzle, I settle on one on which normative uncertainty amounts to uncertainty about what we want. The second topic the chapter addresses is reasoning with desire. I focus on the instrumentalist view that there is no such thing as rational change in ultimate desires. This might seem to be inconsistent with desire-as-belief. But I argue that instrumentalism is mistaken. The argument runs via the claim that with some desires it is indeterminate whether they are instrumental or not, and this makes space for reasoning so as to determine which they are.

This chapter begins with a common objection to desire-as-belief: don't animals have desires, but no beliefs about reasons? Evaluating this objection is difficult, since it raises much wider questions about concept possession and about the mental lives of animals. I do my best: I sketch a version of conceptual role semantics and apply it to reasons beliefs, effectively arguing that a creature has the concept of a reason if they have the right dispositions. I then argue that animals have some of those dispositions to some degree, and thereby count as borderline cases of creatures with the concept of a reason, and borderline cases of creatures with desires. This last claim might seem surprising - aren't they clear-cut desirers? - but I supply some reasons for thinking it plausible.

This chapter considers the debate between objectivist views on which normative reasons are independent of our desires, and subjectivist views, on which they are almost wholly dependent on our desires. I rehearse two classic problems for subjectivism, and then explain away its appeal: subjectivism seems plausible just because it is close to a plausible claim about (structural) rationality. Finally, I discuss desire-based theories of wellbeing, and explain how desire-as-belief supports classic objections to that view.

The appendix discusses David Lewis' famous argument against desire-as-belief. Partly by appeal to claims from chapter 8, I argue that his objection fails.