"What's the worst that can happen?" goes the optimistic saying. It's probably a bad question to ask anyone with a creative imagination. Let's consider the problem on an individual level: it's not really the worst that can happen, but would nonetheless be fairly bad, if you were horribly tortured for a number of years. This is one of the worse things that can realistically happen to one person in today's world.
What's the least bad, bad thing that can happen? Well, suppose a dust speck floated into your eye and irritated it just a little, for a fraction of a second, barely enough to make you notice before you blink and wipe away the dust speck.
For our next ingredient, we need a large number. Let's use 3^^^3, written in Knuth's up-arrow notation:
- 3^3 = 27.
- 3^^3 = (3^(3^3)) = 3^27 = 7625597484987.
- 3^^^3 = (3^^(3^^3)) = 3^^7625597484987 = (3^(3^(3^(... 7625597484987 times ...)))).
3^^^3 is an exponential tower of 3s which is 7,625,597,484,987 layers tall. You start with 1; raise 3 to the power of 1 to get 3; raise 3 to the power of 3 to get 27; raise 3 to the power of 27 to get 7625597484987; raise 3 to the power of 7625597484987 to get a number much larger than the number of atoms in the universe, but which could still be written down in base 10, on 100 square kilometers of paper; then raise 3 to that power; and continue until you've exponentiated 7625597484987 times. That's 3^^^3. It's the smallest simple inconceivably huge number I know.
Now here's the moral dilemma. If neither event is going to happen to you personally, but you still had to choose one or the other:
Would you prefer that one person be horribly tortured for fifty years without hope or rest, or that 3^^^3 people get dust specks in their eyes?
I think the answer is obvious. How about you?
I'll go ahead and reveal my answer now: Robin Hanson was correct, I do think that TORTURE is the obvious option, and I think the main instinct behind SPECKS is scope insensitivity.
Some comments:
While some people tried to appeal to non-linear aggregation, you would have to appeal to a non-linear aggregation which was non-linear enough to reduce 3^^^3 to a small constant. In other words it has to be effectively flat. And I doubt they would have said anything different if I'd said 3^^^^3.
If anything is aggregating nonlinearly it should be the 50 years of torture, to which one person has the opportunity to acclimate; there is no individual acclimatization to the dust specks because each dust speck occurs to a different person. The only person who could be "acclimating" to 3^^^3 is you, a bystander who is insensitive to the inconceivably vast scope.
Scope insensitivity - extremely sublinear aggregation by individuals considering bad events happening to many people - can lead to mass defection in a multiplayer prisoner's dilemma even by altruists who would normally cooperate. Suppose I can go skydiving today but this causes the world to get warmer by 0.000001 degree Celsius. This poses very little annoyance to any individual, and my utility function aggregates sublinearly over individuals, so I conclude that it's best to go skydiving. Then a billion people go skydiving and we all catch on fire. Which exact person in the chain should first refuse?
I may be influenced by having previously dealt with existential risks and people's tendency to ignore them.
"In the absence of other considerations, you have no preference whether or not people get a dust speck in their eye?"
I can regard the moral significance as zero. I don't have to take the view that morality "is" preferences, of any kind or degree.
Excessive demandingness is a famous problem with utiltarianism: rounding down helps to curtail it.