Thanks a lot for the response, Jason! It seems like we actually agree more than it seemed.

if I were to put on my hierarchical hat, I would suggest that so long as the intrinsic characteristics that determine moral status are distinct from the characteristics that determine capacity for welfare, the double-counting worry can be avoided.

Agreed. If we accept the possibility you suggest, then I can see how status-adjusted welfare doesn't run into double-counting. The question is: what makes these status-conferring characteristics morally relevant if not their contribution to welfare? Some views, I suppose, hold that the mere possession of some intrinsically valuable features—supposedly, rationality, autonomy, being created by God, being human, and whatnot—determine moral status even if they don't contribute to welfare. That's a coherent kind of view, and perhaps you're right that a view like this would not necessarily be arbitrary, but I have a hard time finding it plausible. I just don't understand why some property should determine how to treat x if it has nothing to do with what can harm or benefit x.

If appeal to differences in moral status is the only way to avoid obligations that one finds deeply counterintuitive, then the appeal isn’t necessarily arbitrary.

Yeah, I understand the motivation behind Kagan's move. His descriptions of the distributive implications of unitarianism do make it look like mice just can't have the same moral status as human beings. But it doesn't follow that the interests of mice should count less. Many other morally relevant facts might explain why we ought not to massively shift resources towards mice. But yes, I can see the appeal of the hierarchical views as a solution to these problems. However, we should be wary of which intuitions shape our response to those sorts of cases (as Sebo argues in his review), or we're just going to construct a view that rationalizes whatever allocation of resources we find acceptable. Sometimes, Kagan's reasoning sounds like: "Come on, we're not going to help rats! Therefore they must have a much lower status than persons."

I’m sympathetic to the view that ultimately moral status is context-sensitive or agent-relative or somehow multidimensional

Me too, very much so. As for practical value, I like Kagan's eventual move towards "practical realism" a lot. There's a similar move in Rachels (2004). A helpful way to think about this, for utilitarians, is in terms of R.M. Hare's two levels of moral thinking, nicely developed for animals in Varner (2012).

Great post! It lays out rigorously a number of important moving parts and will definitely move the conversation forward.

I'm worried about relying too heavily on Kagan (2019). I found his book thought-provoking, clever and illuminating in many ways, but it shouldn't serve as a point of reference or an entry point for discussions of moral status. For one thing, it's extremely recent. More importantly, Kagan has engaged with, much less cited, very little of the literature (he's candid about it, but I still think that's an issue). As a result, he has a highly idiosyncratic conception of moral status. My main worry with his view is one you note: double counting. But I fail to see how the idea of status-adjusted welfare does not reproduce this problem. In fact, it seems built into your definition of moral status:

For our purposes, I’ll let moral status be the degree to which the interests of an entity with moral standing must be weighed in (ideal) moral deliberation or the degree to which the experiences of an entity with moral standing matter morally.

But that's already stacking the deck against the idea that the strength of the reasons provided by interests depends on the nature of those interests, which may determine moral status. Instead, you seem to be presupposing that moral status determines how much those interests matter even when they're similar. But one shouldn't have to argue that unitarianism is true to find that definition plausible. However, I only find it plausible on the condition that hierarchical views as you spell them out are false.

I also happen to have a minority view of moral status, which aligns with Rachels' (2004), albeit for different reasons (for instance, I reject his moral individualism, but that's another can of worms; see Delon 2014 and 2015). On this view (but also see e.g. Sachs 2011, and to some extent DeGrazia 2008), moral status consists in what treatment is owed by moral agents to the bearers of moral status. Likewise, Sebo (2017) argues that agency makes a difference to moral status with respect to how agents ought to be treated, but as far as know Jeff is a unitarian (see his review of Kagan). Our obligations to different animals may be stronger, based on a number of factors, including their capacity for welfare, and so you might think this means moral status varies according to capacity for welfare. In a sense, yes, but that's where it ends. Yes, moral status can be a matter of degree, but this doesn't commit one to Kagan's double-counting hierarchy. You can't also have capacity for welfare tell you how much the interests of the bearer of moral status count—that's double counting. It seems to me that that's exactly what status-adjusted welfare does. As you note, for unitarians, this collapses into welfare, but that's only on the surface—they still have to compute welfare as you suggest, which I think many would deny. On the other hand, you could have a hierarchical view without double counting: it's just the view that tells you that creatures with greater capacity for welfare give us stronger reasons to protect them. The explanation may be that their interests are more numerous, complex, or strong, which is compatible with the principle of equal consideration. In fact, I think Singer has a hierarchical theory of moral status for all intents and purposes. The claim that similar interests count equally is ultimately what Kagan wants to reject and I don't understand why, nor how he can do this non-arbitrarily or without double-counting.