The principle of justice is deeply rooted in Western thought. Traditionally, it reflects our notoriously vague notions about "fairness." In his Nicomachean Ethics, Aristotle observed that there are basically two spheres of justice: "justice in retribution" and "justice in distribution." However, both spheres are subject to a single formal principle of justice, which states that "equals should be treated equally and that unequals should be treated unequally," or in other words, "we ought to receive, no more, nor less than we deserve." Whenever we develop moral arguments about retributive or distributive justice, we naturally invoke the formal principle. This formal principle obviously leaves us in the dark concerning which individuals are, in fact, equals and how much pleasure or pain they deserve.
Material principles of justice link the formal concept to the real world. In the history of ethics, there are several recurring material principles, or patterns that human beings invoke when they justify one distribution rather than another. These patterns are: merit, equality, need, and social utility.
The principle of merit says that a just society is one where the best people get the most, and the worst people get the least. Meritocracy, therefore, implies hierarchical social arrangements, where the best persons occupy the higher rungs and the lower persons the lower rungs. All societies distribute at least some things based on merit, such as: Superbowl rings, doctoral degrees, driver‟s licenses, and merit scholarships. Even if we wanted to, it would probably be impossible to separate merit from our idea of justice. Unfortunately, merit can mean many different things to different individuals and societies. We are all egoists, therefore, all tend to believe that we as individuals, our families, and our friends, are best and deserve to occupy those higher rungs.
The principle of equality states that at least some things in life ought to be distributed equally. Under normal circumstances, we usually divide up a pizza based on this principle. Egalitarianism implies that at least some social goods ought to be distributed equally. The problem lies in determining exactly what social goods ought to be redistributed equally, and what social goods ought to be distributed based on some other pattern such as, merit, need, or social utility. Clearly some things should not be distributed based on equality:
The principle of need states that resources ought to be distributed to each person according to individual need. Hence, rather than divide up that pizza equally, or based on merit, we might decide that it‟s fair to give most of that pizza, or all of it, to a friend (or stranger) who hasn‟t eaten in a week. We usually try to distribute things like chemo-therapy, welfare checks, and some scholarships based on need. There are some that will argue, unpersuasively, that everything should be distributed based on need. But that‟s extremely messy. The underlying assumption is that we can objectively determine who is truly in need. Of course, one might argue that the fact that you are in need, may or may not be a good reason for others to fill that need. It may or may not be unfair if you are currently in need because of your own bad decisions. If I‟m in need of food because I spent all of my money on lottery tickets, it probably doesn't make much sense for me to claim that my hunger is unjust. But then again, one might argue that gambling is a disease and that the Ohio Lottery generates need. Libertarians are usually willing to help fulfill the needs of others, but not unconditionally. If someone is in need because of forces beyond their control, libertarians might be willing to provide temporary assistance. But, as I stated earlier, they are loath to set up a public system comprised of beneficiaries supported by benefactors.
The distributive principle of social utility holds that we ought to distribute at least some things in such a way as to maximize a favorable balance between pain and pleasure in the whole community. Hence, we might decide to immunize all inner-city children in Cincinnati against certain diseases, regardless of merit, equality, or need, in order to minimize the long term social costs associated with treating them for preventable diseases later on.
Of course, the basic problem of justice is how to determine which material principle, or pattern, is relevant to the distribution of which particular resource. If I were to offer a scholarship to attend the Mount, should I award it based on social utility (cost-benefit), equality (have a lottery), merit (administer a test), or need (check your annual income)? Of course, different persons will benefit from the scholarship, depending on which material principle is invoked. So in the final analysis, one might ask: "Who really deserves that scholarship?" Libertarians argue that society ought to refrain from all redistribution schemes (equality, need, utility, merit) and allow the free market to do the distributing. In a free market, I can own a Mercedes Benz automobile, or perhaps more likely, a Gibson ES 335 electric guitar, if I am willing to pay the market price for it.
Justice in retribution embraces the familiar notion of "an eye for an eye, and a tooth for a tooth," otherwise known as the principle of proportionality. We are morally obligated to praise and blame others in proportion to what they deserve. Justice, therefore, requires that we get no more, nor less, than we deserve. Justice in retribution involves the familiar concept of payback. When we think about justice in retribution we most often apply it to our response to wrongdoing, and reduce it to the familiar maxim: "the punishment must fit the crime."
Justice in distribution carries with it the idea that there are better and worse ways to distribute pleasures and pains within a community. Again, it says that we ought to get "no more, nor less than we deserve." Hence, we suffer from an injustice when we either get more or less than we deserve. Of course, we don‟t often complain when we get more of a good thing than we deserve or when we get less of a bad thing than we actually deserve.
When philosophers and economists talk about distributive justice, they usually distinguish between various classes of things that are subject to just or unjust distribution. One such distinction differentiates between human wants or desires, on the one hand, and needs, or primary goods, or resources, on the other. The principle of justice in distribution is only applicable under conditions of scarcity. When everyone has as much of something as they need or want, they usually do not complain of injustice. If Charles Darwin was right, we can expect a biological world characterized by scarce resources and competition between organisms to possess those resources. For human beings and some animals, possession of resources generally brings pleasure and the lack of resources, pain. Nature distributes resources based on "natural selection;" (John Rawls calls it the "Natural Lottery") the strong get the resources and the weak generally do not. Is that fair? Is Mother Nature fair in her dealings with human beings? The principle of distributive justice comes into play when we humans decide collectively not to live under Darwinian rule, but instead, decide to redistribute resources and the pains and pleasures associated with them, based on justice.