I agree with blacktrance's reply to you, and also see my reply to tog in a different subthread for some commentary. However, I'm sufficiently unsure of what you're saying to be certain that your comment is fully answered by either of those things. For example:

HUs who think that you are simply caring about different things

If you [the hypothetical you] think that it's possible to care (intrinsically, i.e. terminally) about things other than pain and pleasure, then I'm not quite sure how you can remain a hedonistic utilitarian. You'd have to say something like: "Yes, many people intrinsically value all sorts of things, but those preferences are morally irrelevant, and it is ok to frustrate those preferences as much as necessary, in order to minimize pain and maximize pleasure." You would, in other words, have to endorse a world where all the things that people value are mercilessly destroyed, and the things they most abhor and despise come to pass, if only this world had the most pleasure and least pain.

Now, granted, people sometimes endorse the strangest things, and I wouldn't even be surprised to find someone on Lesswrong who held such a view, but then again I never claimed otherwise. What I said was that I should hope those people do not impose such a worldview on me.

If I've misinterpreted your comment and thereby failed to address your points, apologies; please clarify.

Hedonistic utilitiarians, however, do not acknowledge that it's possible, or that it's valid, to care about things that are not pain or pleasure.

They may think it's incorrect if they're realists, or cognitivists of some other form. But this has nothing to do with their being HUs, only with their being cognitivists.

No, I don't think this is right. I think you (and Kaj_Sotala) are confusing these two questions:

1. Is it correct to hold an ethical view that is something other than hedonistic utilitarianism?
2. Does it make any sense to intrinsically value anything other than pleasure, or intrinsically disvalue things other than pain?

#1 is a meta-ethical question; moral realism or cognitivism may lead you to answer "no", if you're a hedonistic utilitarian. #2 is an ethical question; it's about the content of hedonistic utilitarianism.

If I intrinsically care about, say, freedom, that's not an ethical claim. It's just a preference. "Humans may have preferences about things other than pain/pleasure, and those preferences are morally important" is an ethical claim which I might formulate, about that preference that I have.

Hedonistic utilitarianism tells me that my aforementioned preference is incoherent or mistaken, and that in fact I do not have any preferences (or any preferences that are morally important or worth caring about) other than preferences about pleasure/pain.

Moral realism (which, as blacktrance correctly notes, is implied by any utilitarianism) may lead a hedonistic utilitarian to say that my aforementioned ethical claim is incorrect.

As for your scenarios, I'm not sure what you meant by listing them. My point was that my scenario, which describes a situation involving a hypothetical me, Said Achmiz, would be bothersome to me, Said Achmiz. Is it really not clear why it would be?

Yes, the "what then" was rhetorical. If I had to express my point non-rhetorically, it'd be something like this:

If you take a position which gives ethically correct results only until such time as some (reasonably plausible) scenario comes to pass, then maybe your position isn't ethical in the first place. "This ethical framework gives nonsensical or monstrous results in edge cases [of varying degrees of edge-ness]" is, after all, a common and quite justified criticism of ethical frameworks.

2016: "In Defense Of Putting Babies In Wood Chippers"

Heck, I could write that post right now. But what's it got to do with truth and such?

At that point ... [various possibilities]

Yeah, I meant that as a normative "what then", not an empirical one. I agree that what you describe are plausible scenarios.

If you say "all that matters is pain and pleasure", and I say "no! I care about other things!", and you're like "nope, not listening. PAIN AND PLEASURE ARE THE ONLY THINGS", and then proceed to enact policies which minimize pain and maximize pleasure, without regard for any of the other things that I care about, and all the while I'm telling you that no, I care about these other things! Stop ignoring them! Other things matter to me! but you're not listening because you've decided that only pain and pleasure can possibly matter to anyone, despite my protestations otherwise...

... well, I hope you can see how that would bother me.

It's not just a matter of us caring about different things. If it were only that, we could acknowledge the fact, and proceed to some sort of compromise. Hedonistic utilitiarians, however, do not acknowledge that it's possible, or that it's valid, to care about things that are not pain or pleasure. All these people who claim to care about all sorts of other things must be misguided! Clearly.

Interestingly, it seems our views are complementary, not contradictory. I would (I think) be willing to endorse what you said as a recipe for implementing the views I describe.

There is no such centralized place, no; I've alluded to my views in comments here and there over the past year or so, but haven't gone laid them out fully. (Then again, I'm a member of no movements that depend heavily on any ethical positions. ;)

Truth be told — and I haven't disguised this — my ethical views are not anywhere near completely fleshed-out. I know the general shape, I suppose, but beyond that I'm more sure about what I don't believe — what objections and criticisms I have to other people's views — than about what I do believe. But here's a brief sketch.

I think that consequentialism, as a foundational idea, a basic approach, is the only one that makes sense. Deontology seems to me to be completely nonsensical as a grounding for ethics. Every seemingly-intelligent deontologist to whom I've spoken (which, admittedly, is a small number — a handful of people here in LessWrong) has appeared to be spouting utter nonsense. Deontology has its uses (see Bostrom's "An Infinitarian Challenge to Aggregative Ethics", and this post by Eliezer, for examples), but there it's deployed for consequentialist reasons: we think it'll give better results. I've seen the view expressed that virtue ethics is descriptively correct as an account of how human minds implement morality, and (as a result) prescriptively valid as a recommendation of how to implement your morality in your own mind once you've decided on your object-level moral views, and that seems like a more-or-less reasonable stance to take. As an actual philosophical grounding for morality, virtue ethics is nonsense, but perhaps that's fine, given the above. Consequentialism actually makes sense. Consequences are the only things that matter? Well, yes. What else could there be?

As far as varieties of consequentialism go... I think intended and foreseeable consequences matter when evaluating the moral rightness of an act, not actual consequences; judging based on actual consequences seems utterly useless, because then you can't even apply decision theory to the problem of deciding how to act. Judging on actual consequences also utterly fails to accord with my moral intuitions, while judging on intended and foreseeable consequences fits quite well.

I tend toward rule consequentialism rather than act consequentialism; I ask not "what would be the consequences of such an act?", but "what sort of world would it be like, where [a suitably generalized class of] people acted in this [suitably generalized] way? Would I want to live in such a world?", or something along those lines. I find act consequentialism to be too often short-sighted, and open to all sorts of dilemmas to which rule consequentialism simply does not fall prey.

I take seriously the complexity of value, and think that hedonistic utilitiarianism utterly fails to capture that complexity. I would not want to live in a world ruled by hedonistic utilitiarians. I wouldn't want to hand them control of the future. I generally think that preferences are what's important, and ought to be satisfied — I don't think there's any such thing as intrinsically immoral preferences (not even the preference to torture children), although of course one might have uninformed preferences (no, Mr. Example doesn't really want to drink that glass of acid; what he wants is a glass of beer, and his apparent preference for acid would dissolve immediately, were he apprised of the facts); and satisfying certain preferences might introduce difficult conflicts (the fellow who wants to torture children — well, if satisfying his preferences would result in actual children being actually tortured, then I'm afraid we couldn't have that). "I prefer to kill myself because I am depressed" is genuinely problematic, however. That's an issue that I think about often.

All that seems like it might make me a preference utilitiarian, or something like it, but as I've said, I'm highly skeptical about the possibility or even coherence of aggregating utility across individuals, not to mention the fact that I don't think my own preferences adhere to the VNM axioms, and so it may not even be possible to construct a utility function for all individuals. (The last person with whom I was discussing this stopped commenting on Lesswrong before I could get hold of my copy of Rational Choice in an Uncertain World, but now I've got it, and I'm willing to discuss the matter, if anyone likes.)

I don't think it's obvious that all beings that matter, matter equally. I don't see anything wrong with valuing my mother much more than I value a randomly selected stranger in Mongolia. It's not just that I do, in fact, value my mother more; I think it's right that I should. My family and friends more than strangers; members of my culture (whatever that means, which isn't necessarily "nation" or "country" or any such thing, though these things may be related) more than members of other cultures... this seems correct to me. (This seems to violate both the "equal consideration" and "agent-neutrality" aspects of classical utilitarianism, to again tie back to the SEP breakdown.)

As far as who matters — to a first approximation, I'd say it's something like "beings intelligent and self-aware enough to consciously think about themselves". Human-level intelligence and subjective consciousness, in other words. I don't think animals matter. I don't think unborn children matter, nor do infants (though there are nonetheless good reasons for not killing them, having to do with bright lines and so forth; similar considerations may protect the severely mentally disabled, though this is a matter which requires much further thought).

Do these thoughts add up to a coherent ethical system? Unlikely. They're what I've got so far, though. Hopefully you find them at least somewhat useful, and of course feel free to ask me to elaborate, if you like.

I was originally only objecting to the argument that aggregating utility between individuals would be impossible or incoherent

Er, hang on. If this is your objection, I'm not sure that you've actually said what's wrong with said argument. Or do you mean that you were objecting to the applicability of said argument to hedonistic utilitarianism, which is how I read your comments?