I am not wholly unsympathetic to the many commenters in Torture vs. Dust Specks who argued that it is preferable to inflict dust specks upon the eyes of 3^^^3 (amazingly huge but finite number of) people, rather than torture one person for 50 years. If you think that a dust speck is simply of no account unless it has other side effects - if you literally do not prefer zero dust specks to one dust speck - then your position is consistent. (Though I suspect that many speckers would have expressed a preference if they hadn't known about the dilemma's sting.)
So I'm on board with the commenters who chose TORTURE, and I can understand the commenters who chose SPECKS.
But some of you said the question was meaningless; or that all morality was arbitrary and subjective; or that you needed more information before you could decide; or you talked about some other confusing aspect of the problem; and then you didn't go on to state a preference.
Sorry. I can't back you on that one.
If you actually answer the dilemma, then no matter which option you choose, you're giving something up. If you say SPECKS, you're giving up your claim on a certain kind of utilitarianism; you may worry that you're not being rational enough, or that others will accuse you of failing to comprehend large numbers. If you say TORTURE, you're accepting an outcome that has torture in it.
I falsifiably predict that of the commenters who dodged, most of them saw some specific answer - either TORTURE or SPECKS - that they flinched away from giving. Maybe for just a fraction of a second before the question-confusing operation took over, but I predict the flinch was there. (To be specific: I'm not predicting that you knew, and selected, and have in mind right now, some particular answer you're deliberately not giving. I'm predicting that your thinking trended toward a particular uncomfortable answer, for at least one fraction of a second before you started finding reasons to question the dilemma itself.)
In "bioethics" debates, you very often see experts on bioethics discussing what they see as the pros and cons of, say, stem-cell research; and then, at the conclusion of their talk, they gravely declare that more debate is urgently needed, with participation from all stakeholders. If you actually come to a conclusion, if you actually argue for banning stem cells, then people with relatives dying of Parkinson's will scream at you. If you come to a conclusion and actually endorse stem cells, religious fundamentalists will scream at you. But who can argue with a call to debate?
Uncomfortable with the way the evidence is trending on Darwinism versus creationism? Consider the issue soberly, and decide that you need more evidence; you want archaeologists to dig up another billion fossils before you come to a conclusion. That way you neither say something sacrilegious, nor relinquish your self-image as a rationalist. Keep on doing this with all issues that look like they might be trending in an uncomfortable direction, and you can maintain a whole religion in your mind.
Real life is often confusing, and we have to choose anyway, because refusing to choose is also a choice. The null plan is still a plan. We always do something, even if it's nothing. As Russell and Norvig put it, "Refusing to choose is like refusing to allow time to pass."
Ducking uncomfortable choices is a dangerous habit of mind. There are certain times when it's wise to suspend judgment (for an hour, not a year). When you're facing a dilemma all of whose answers seem uncomfortable, is not one of those times! Pick one of the uncomfortable answers as the best of an unsatisfactory lot. If there's missing information, fill in the blanks with plausible assumptions or probability distributions. Whatever it takes to overcome the basic flinch away from discomfort. Then you can search for an escape route.
Until you pick one interim best guess, the discomfort will consume your attention, distract you from the search, tempt you to confuse the issue whenever your analysis seems to trend in a particular direction.
In real life, when people flinch away from uncomfortable choices, they often hurt others as well as themselves. Refusing to choose is often one of the worst choices you can make. Motivated continuation is not a habit of thought anyone can afford, egoist or altruist. The cost of comfort is too high. It's important to acquire that habit of gritting your teeth and choosing - just as important as looking for escape routes afterward.
Hmm. I seem to be flinching away from both answers, and I think I know why. It's because I'm unable to decide whether utility really does multiply (after all, one could advocate the utility function "The minimum happiness within the population", instead of the sum).
So I'm happy to make the factual claims that "Sum-utility => pick 'torture'" and "Min-utility => pick 'specks'"; I just can't see any procedure for choosing between sum and min. So I'll formulate a test to see which I believe: I'll gradually reduce the severity of the non-speck option. So, specks versus someone getting tortured for 25 years, I'm still unsure. Specks versus someone getting slapped in the face, I choose slap over specks. Therefore I'm not following min-utility, so I'm willing to accept that really I'm following sum-utility, so in the original problem I pick Torture. I don't like this, because my brain wants to be scope-insensitive and refuses to understand 3^^^3, but when I made one of the outcomes not flinch-worthy that outcome got picked, and I'm pretty sure that my reasons for picking Slap ought to scale up to Torture, so there it is.
I started this post not knowing what answer I would reach despite having spent several minutes on the question. I think I've now been trying to resolve this for over half an hour, and I still feel uncomfortable. My mind has just now come up with a third alternative, which is that utilities should perhaps be rated with hyperreals, so that 3^^^3 1 is still less than 1 H (for an infinite hyperinteger H), in which case we could pick Specks without discarding sum-utility. But I probably wouldn't have thought of that while I was locked up and couldn't choose an answer. I am now feeling comfortable, which suggests that this is what I actually believe about utilities. Of course, now there is an experiment I could do to try and falsify this: try to construct a chain of things starting at a dust speck and ending at torture, where each link in the chain is only a finite amount worse than the one before. I know I can get from speck to slap, because I chose Slap over Specks. I also think a hefty kick up the arse is only finitely worse than a slap. I next try to get to a broken arm, but I'm unwilling to do that (at least, in a single step), so I need to find something intermediate. In fact I think I should try and find something I can jump down to from a broken arm, because a broken anything seems scary in a new way. A deep-bruised hand? Yes, I think that relates finitely to a broken arm. I also think that finitely many kicks up the arse are worse than a deep-bruised hand. Given that my instinctive feeling about the relation of kick to arm was very similar to my feeling about the relation of speck to torture, I conclude that in fact my scale of utilities is constrained to the finite.
The point to this post (if there is one) is that a useful method seems to be to vary the parameters of the problem until you can get an answer, and then look to see whether that illuminates the original problem. (Come to think of it, ISTR that's one of Polyà's How To Solve It tips.) But to evaluate this method, I need to see whether it can also produce the opposite result. So, I need to vary the parameters in ways that favour Specks. If I reduce the 3^^^3 to something smaller, I eventually pick Specks because I get a number I think I can comprehend - but that number has to be so much smaller than 3^^^3 that I don't think it's relevant to the original problem. If I make the 'torture' option involve something worse than torture, I still pick it - I can't think of anything that's sufficiently worse than torture that doing that to someone could make me pick Specks when I didn't pick Specks against torture.
So the method does constrain, and I pick Torture. There, finally finished this post.
Of course, you can also use the chain of negative-utility cases to make a direct argument for specks vs. torture.
Say you prefer 1 slap to N1 specks. Then you prefer 1 kick to N2 slaps, 1 bruise to N3 kicks, 1 broken arm to N4 bruises, and so on, up until the last step where you prefer years of torture to Nk of something.
It follows that the specks vs. torture point comes at N1 x N2 x N3 x .... x Nk. This is pretty much always going to be less than 3^^^3 -- if the steps were truly small, the factors are all going to be less than a trillion or so, and there's probably going to be less than a trillion steps, and (1 trillion)^(1 trillion) is still insignificant compared to 3^^^3.