" By giving the double dose to the more seriously injured person, we bring about a situation in which there is less difference in the degree of suffering felt by the two victims than there would be if we gave one dose to each. Instead of ending up with one person in considerable pain and one in no pain, we end up with two people in slight pain. This is in line with the principle of declining marginal utility, a principle well-known to economists, which states that the more someone has of something, the less she will gain from an additional quantity of it. "

― Peter Singer , Practical Ethics