"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?
Eliezer, a problem seems to be that the speck does not serve the function you want it to in this example, at least not for all readers. In this case, many people see a special penny because there is some threshold value below which the least bad bad thing is not really bad. The speck is intended to be an example of the least bad bad thing, but we give it a badness rating of one minus .9-repeating.
(This seems to happen to a lot of arguments. "Take x, which is y." Well, no, x is not quite y, so the argument breaks down and the discussion follows some tangent. The Distributed Republic had a good post on this, but I cannot find it.)
We have a special penny because there is some amount of eye dust that becomes noticeable and could genuinely qualify as the least bad bad thing. If everyone on Earth gets this decision at once, and everyone suddenly gets >6,000,000,000 specks, that might be enough to crush all our skulls (how much does a speck weigh?). Somewhere between that and "one speck, one blink, ever" is a special penny.
If we can just stipulate "the smallest unit of suffering (or negative qualia, or your favorite term)," then we can move on to the more interesting parts of the discussion.
I also see a qualitative difference if there can be secondary effects or summation causes secondary effects. As noted above, if 3^^^3/10^20 people die due to freakishly unlikely accidents caused by blinking, the choice becomes trivial. Similarly, +0.000001C sums somewhat differently than specks. 1 speck/day/person for 3^^^3 days is still not an existential risk; 3^^^3 specks at once will kill everyone.
(I still say Kyle wins.)