If a decision decreases utility, is it not irrational?
I don't see how you could go about proving this.
As for the trolley problem, what we are dealing with is the aftermath of the trolley problem. If you save the people on the trolley, it could be argued that you have behaved dishonourably, but what about the people you saved? Surely they are innocent of your decision. If humanity is honourably wiped out by the space monsters, is that better than having some humans behave dishonourably and others (i.e. those who favoured resistance, but were powerless to effect it) survive honourably?
Well, wait. Are we dealing with the happiness that results in the aftermath, or are we dealing with the moral value of the actions themselves? Surely these two are discrete. Don't the intentions behind an action factor into the morality of the action? Or are the results all that matter? If intentions are irrelevant, does that mean that inanimate objects (entities without intentions, good or bad) can do morally good things? If a tornado diverts from a city at the last minute, was that a morally good action?
I think intentions matter. It might be the case that, 100 years later, the next generation will be happier. That doesn't mean that the decision to sacrifice those children was the morally good decision-- in the same way that, despite the tornado-free city being a happier city, it doesn't mean the tornado's diversion was a morally good thing.
I should have said "decreases personal utility." When I say rationality, I mean rationality. Decreasing personal utility is the opposite of "winning".
It's just possible that some lesswrong readers may be unfamiliar with Torchwood: It's a British sci-fi TV series, a spin-off from the more famous, and very long-running cult show Dr Who.
Two weeks ago Torchwood Series 3 aired. It took the form of a single story arc, over five days, shown in five parts on consecutive nights. What hopefully makes it interesting to rationalist lesswrong readers who are not (yet) Whovians was not only the space monsters (1) but also the show's determined and methodical exploration of an iterated Trolley Problem: in a process familiar to seasoned thought-experimenters the characters were tested with a dilemma followed by a succession of variations of increasing complexity, with their choices ascertained and the implications discussed and reckoned with.
An hypothetical, iterated rationalist dilemma... with space monsters... and monsters a great deal more scary - and messier - than Omega - what's not to like?
So, on the off chance that you missed it, and as a summer diversion from more academic lesswrong fare, I thought a brief description of how a familiar dilemma was handled on popular British TV this month, might be of passing interest (warning: spoilers follow)
The details of the scenario need not concern us too much here (and readers are warned not too expend too much mental energy exploring the various implausibilities, for want of distraction) but suffice to say that the 456, a race of evil aliens, landed on Earth and demanded that a certain number of children be turned over to them to suffer a horrible fate-worse-than-death or else we face the familiar prospects of all out attack and the likely destruction of mankind.
Resistance, it almost goes without saying, was futile.
The problems faced by the team could be roughly sorted into some themes
The Numbers dilemma - is it worth sacrificing any amount of children to save the rest?
The Quality dilemma: does it make any difference which children?
The choice dilemma: how should the sacrifical cohort be chosen?
The limits of human rationality: are there certain 'rational' decisions that are simply too much to expect a human being to be able to make?
Actually despite my jocular tone in the first paragraph I don't want to make too light of this series, as it was disturbing viewing.
Anyway: that being said: rationalist lesswrong community members may want to think dispassionately about the their answers before I reveal the conclusions that Russell T Davies (the writer) came to:
Numbers
Quality
Choice
This was handled by the politicians who considered two dimensions in the selection:
Rationality at the limit
On the question of 'how close' a straightforward evolutionary approach was used. Children of the decision-makers were safe, and grandchildren.
"And our nephews?" "Don't push it".
But the limits of rationality, it seems, are dependent upon gender: While it was recognised that no woman could be expected to agree to the rational sacrifice of her child, it was expected by some that men might have to, and in the end the main character - male - sacrificed a grandchild.
And that's it. Perhaps not a complete disposal of the trolley problem, but nevertheless an interesting excursion into the realms of philosphical dilemmas for a popular drama. Rationalism is a meme - pass it on.
(1) like many TV aliens: surprisingly able to construct spaceships without the benefit of an opposable thumb (2) Yes, that was actually the 1965 back-story.