I am sick and tired of hearing about that ticking nuclear bomb in Manhattan. You know the one. Why? Because, if you let me put my thumb on the utilitarian scales, I can get you to agree that you have an affirmative moral duty to torture a three-year-old child to death.
I will utilitze my mighty powers of stipulation, thusly: the earth is invaded by a race of super-intelligent, but malevolent beings.
Go read the rest.