Questions arise daily about how wealth and goods should be allocated. Given the relative scarcity of society’s resources, deciding how these resources should be distributed is an important moral task. Should everyone receive roughly the same amount? Or should people be rewarded according to how hard they work or how much they contribute to society? To what extent should economic distribution take need into account? For example, with modern technology at their disposal, today’s hospital are able to perform life-prolonging feats of medicine that were undreamed of only a couple of decades ago, but these services are often extraordinarily costly. Who, then, should have access to them? Those who can afford them? Any who need them? Those who are most likely to benefit.
One way unfairness creates injustice is when like cases are not treated alike. This principle of justice does not say whether we are to assume equality of treatment until some difference between cases is shown or to assume the opposite until some relevant similarities are demonstrated, or claim of claim of injustice based on equality is meant to place the burden of proof on those who would endorse unequal treatment. Still, the premise that all persons are equal does not establish a direct relationship between justice and economic distribution. We all believe that some differences in the treatment of persons are consistent with equality (punishment, for example) and neither respect for equality nor a commitment to equal treatment necessarily implies an equal distribution of economic goods.
Among the principles most frequently recommended as a basis of distribution are: to each an equal share, to each according to social contribution, and to each according to merit. Everyone of these principles has it advocates, and each seems plausible in some circumstances. But only in some. There are problems with each. For example, if equality of income were guaranteed, then the lazy would receive as much as the industrious. One the other hand, effort is hard to measure and compare, and what one is able to contribute to society may depend on one’s luck in being at the right place at the time. And so on. No single principle seems to work in enough circumstances to be defended successfully as the sole principle of justice in distribution.
Multiple principles may often be relevant to a single situation. Some times they may pull in the same direction, as when wealthy professionals such as doctors defend their high incomes simultaneously on grounds of superior effort, merit, social contribution, and even (because of high cost of malpractice insurance) need. Or the principle may pull in different directions, as when a teacher must balance effort against against performance in assigning grades to pupils, Prima Facie principle of just distribution -equality, need effort and so on -and one must try to find the principle that best applies in the given circumstances. If several principles seem to apply, then one must simply weigh them the best one can.