Consider the following question posed by Amartya Sen, winner of the 1998 Nobel Prize in Economics. Three men have come to you looking for work. You have only one job to offer; the work cannot be divided among the three of them and they are all equally qualified. One of your goals is to make the world a better place by hiring the man who needs the job most.
The first man is the poorest of the three. If improving human welfare is your primary aim, then presumably he should get the job. Or maybe not. The second man is not the poorest, but he is the unhappiest because he has only recently become poor and he is not accustomed to deprivation. Offering him the job will cause the greatest gain in happiness.
The third man is neither the poorest nor the unhappiest. But he has a chronic health problem, borne stoically for his whole life, that can be cured with the wages from his job. Thus, giving him the job would have the most profound effect on an individual’s quality of life.
Who should get the job?