A buck-passing theory of the value says that the good is that which would be desired by a subject with an idealised psychology. In Smith's telling, "idealised psychology" is typically cashed out in terms of "rational requirements" and other ideals of reason, which are supposedly something philosophers should be able to understand a priori. I don't understand why there's a drive to a priori here. If I were wondering what an ideal psychology looks like, I would look to the world, for examples of flourishing individuals. This assumes I have some latent capability to recognise ideal examples, but that doesn't seem less plausible than claiming I can recognise principles of ideal rationality a priori. So I would look for people whose psychologies seem adaptive and virtuous. I suppose there's a worry about circularity here. And you might wonder why "adaptive" has any conceptual connection to "good". My instinct is to say: whatever. I'm nervous about thinking in terms of a single ideal psychology. Humanity is a work in progress....we should not expect to be able to give a complete account of the good just yet... or ever? Buck passing theories satisfy my strong intuition that valuing requires a valuer. What are some major objections to this position? Grounding notion of ideal psychology seems hard, don't you end up with many different ideals? My guess is yes, and that's fine. So for me, I end up with a conflict theory. ### Michael Smith on Sidgwick > the Sidgwickian definition of ‘good’ is, in Scanlon's (1998) terms, a buck-passing theory (see also the various theories discussed in Rabinowicz and Rønow-Rasmussen 2004). It entails that there is no metaphysically independent property of goodness, but rather that something's being good is a matter of its being an object of the desires that the subject would have if that subject had an idealized psychology. The definitional buck is in this way passed from the concept of goodness to the concept of an idealized psychology: the latter is the definitionally basic concept.13 When we say that agents who claim to have reasons to act in a certain way must be prepared to specify some desirable feature brought about by their acting in that way, it is just very plausible to interpret this as the demand that people explain why the thing that they claim to have reason to do is something that they (p. 20) ought to desire: as the demand, in other words, that they would desire that thing if their psychology met rational requirements and other ideals of reason. The most basic normative judgement is the claim that an agent's psychology meets all rational requirements and ideals of reason. PH: plurality of such psychologies? > According to Henry Sidgwick (1907), the good is not metaphysically simple, but is rather a matter of what we ought to desire (Hurka 2003). […] Something's being of value is defined in terms of those desires that are possessed by one whose psychology is ideal, that is, a psychology that meets all rational requirements and other ideals of reason. Sidgwick defines the good as that which *would* be desired by an agent if they met the requirements of rationality and other ideals of reason. > (x)(t)(x at t has all-things-considered reason to φ in circumstances C iff φ-ing is the unique action of those x can perform at t that brings about what x would desire most happens in C if his psychology met all rational requirements and ideals of reason) On Sidgwick's account: > when we talk of a thing's being good we must, at least implicitly, be talking about that thing's being good relative to people and times, namely, all of those who ought, at those times, to desire that thing. This is an example of what Scanlon calls a buck-passing theory of value, which: > entails that there is no metaphysically independent property of goodness, but rather that something's being good is a matter of its being an object of the desires that the subject would have if that subject had an idealized psychology. The definitional buck is in this way passed from the concept of goodness to the concept of an idealized psychology: the latter is the definitionally basic concept. When we say that: > agents who claim to have reasons to act in a certain way must be prepared to specify some desirable feature brought about by their acting in that way, it is just very plausible to interpret this as the demand that people explain why the thing that they claim to have reason to do is something that they (p. 20) ought to desire: as the demand, in other words, that they would desire that thing if their psychology met rational requirements and other ideals of reason How do we figure out what it looks like for a psychology to meet rational requirements and other ideals of reason? > It is immensely difficult to provide a comprehensive list of all of the rational requirements to which a psychology is subject or an account of what all of the ideals of reason are. Though most would agree that these requirements include the requirements and ideals of coherence, unity, and informedness, as soon as any concrete proposal is made about what these requirements amount to, the proposals are hotly contested (Gibbard 1990; Blackburn 1998). The article only considers a priori arguments for what constitute rational requirements and other ideals of reason. **Why**?? A big thing missing from this article, which I was looking for, was discussion of evolutionary psychology and what that implies for (moral) philosophy.