This is not the post I was planning to write. Originally, it was going to be a heroic post where I showed my devotion to philosophical principles by reluctantly but fearlessly biting the bullet on the sadistic conclusion. Except... it turns out to be nothing like that, because the sadistic conclusion is practically void of content and embracing it is trivial.
Sadism versus repugnance
The sadistic conclusion can be found in Gustaf Arrhenius's papers such as "An Impossibility Theorem for Welfarist Axiologies." In it he demonstrated that - modulo a few technical assumptions - any system of population ethics has to embrace either the Repugnant Conclusion, the Anti-Egalitarian Conclusion or the Sadistic conclusion. Astute readers of my blog posts may have noticed I'm not the repugnant conclusion's greatest fan, evah! The anti-egalitarian conclusion claims that you can make things better by keeping total happiness/welfare/preference satisfaction constant but redistributing it in a more unequal way. Few systems of ethics embrace this in theory (though many social systems seem to embrace it in practice).
Remains the sadistic conclusion. A population ethics that accepts this is one where it is sometimes better to create someone whose life is not worth living (call them a "victim"), rather a group of people whose lives are worth living. It seems well named - can you not feel the top hatted villain twirl his moustache as he gleefully creates lives condemned to pain and misery, laughing manically as he prevents the intrepid heroes from changing the settings on his incubator machine to "worth living"? How could that sadist be in the right, according to any decent system of ethics?
Remove the connotations, then the argument
But the argument is flawed, for two main reasons: one that strikes at the connotations of "sadistic", the other at the heart of the comparison itself.
The reason the sadistic aspect is a misnomer is that creating a victim is not actually a positive development. Almost all ethical systems would advocate improving the victim's life, if at all possible (or ending it, if appropriate). Indeed some ethical systems which have the "sadistic conclusion" (such as prioritarianism or egalitarianism) would think it more important to improve the victim's life that some ethical systems that don't have the conclusion (such as total utilitarianism). Only if such help is somehow impossible do you get the conclusion. So it's not a gleeful sadist inflicting pain, but a reluctant acceptance that "if universe conspires to prevent us from helping this victim, then it still may be worth creating them as the least bad option" (see for instance this comment).
"The least bad option." For the sadistic conclusion is based on a trick, contrasting two bad options and making them seem related (see this comment). Consider for example whether it is good to create a large permanent underclass of people with much more limited and miserable lives than all others - but whose lives are nevertheless just above some complicated line of "worth living". You may or may not agree that this is bad, but many people and many systems of population ethics do feel it's a negative outcome.
Then, given that this underclass is a bad outcome (and given a few assumptions as to how outcomes are ranked) then we can find other bad outcomes that are not quite as bad as this one. Such as... a single victim, a tiny bit below the line of "worth living". So the sadistic conclusion is not saying anything about the happiness level of a single created population. It's simply saying that sometime (A) creating underclasses with slightly worthwhile lives can sometimes be bad, while (B) creating a victim can sometimes be less bad. But the victim isn't playing a useful role here: they're just an example of a bad outcome better than (A), only linked to (A) through superficial similarity and rhetoric.
For most systems of population ethics the sadistic conclusion can thus be reduced to "creating underclasses with slightly worthwhile lives can sometimes be bad." But this is the very point that population ethicists are disputing each other about! Wrapping that central point into a misleading "sadistic conclusion" is... well, the term "misleading" gave it away.
I'm not saying that our population intuitions are simple, I'm saying that we can't rule out the possibility. For example a prior I wouldn't have expected physics to turn out to be simple, however (at least to the level that I took it) physics seems to be remarkably simple (particularly in comparison to the universe it describes), this leads me to conclude that there is some mechanism by which things turn out to be simpler than I would expect.
To give an example, my best guess (besides "something I haven''t though of") for this mechanism is that mathematical expressions are fairly evenly distributed over patterns which occur in reality, and that one should hence expect there to be a fairly simple piece of mathematics which comes very close to describing physics, a similar thing might happen with our population intuitions.
Wouldn't highly abstract aspects of our psychology be be more recent and as such simpler?
This depends on your priors. If you assign comparable probabilities to simple and complex hypothesis, this follows. If you assign higher probabilities to simple hypothesis than complex ones it doesn't.
If you flip 1000 fair coins, the resulting output is more likely to be a mishmash of meaningless clumps than it is to be something like "HHTTHHTTHHTTHHTT..." or another very simple repeating pattern. Similarly, a chaotic[1] process like the evolution of our ethical intuitions is more likely to produce an arbitrary mishmash of conflicting emotion... (read more)