Desert in philosophy is the condition of being deserving of something, whether good or bad. It is related to justice, revenge, blame, punishment and many topics central to moral philosophy. In ordinary usage, to deserve is to earn or merit a reward; in philosophy, the distinction is drawn in the term desert to include the case that that which one receives as one's just deserts may well be unwelcome, or a reward. For example, if one scratches off a winning lottery ticket, one may be entitled to the money, but one does not necessarily deserve it in the same way one would deserve $5 for mowing a lawn, or a round of applause for performing a solo.
A general formula for desert claims is this: Thing A deserves X in virtue of Y. For example, I (A) deserve a good grade on my test (X) because I studied hard (Y); Cincinnati (A) deserves to be praised (X) because it is a pretty city (Y). Some authors have added a further criteria, qualifying Y. That is, Agent A deserves X in virtue of Y if and only if A is responsible for Y (or, alternatively, if A is also deserving of Y). For example, one does not deserve respect simply because one is a human being, because one is not responsible for being a human being (Y) -- arguments such as this are understandably contentious. Alternatively, if one uses steroids to win in a footrace, one does not deserve to win because one does not deserve increased physical abilities.
One of the most controversial rejections of the concept of desert was made by the political philosopher John Rawls. Rawls, writing in the mid to late twentieth century, claimed that a person cannot claim credit for being born with greater natural endowments (such as superior intelligence or athletic abilities), as it is purely the result of the 'natural lottery'. Therefore, that person does not morally deserve the fruits of his or her talents and/or efforts, such as a good job or a high salary. However, Rawls was careful to explain that, even though he dismissed the concept of moral Desert, people can still legitimately expect to receive the benefits of their efforts and/or talents. The distinction here lies between Desert and, in Rawls' own words, 'Legitimate Expectations'.
Rawls' remarks about natural endowments provoked an often-referred response by Robert Nozick. Nozick claimed that to treat peoples' natural talents as collective assets is to contradict the very basis of the deontological liberalism Rawls wishes to defend, i.e. respect for the individual and the distinction between persons. Nozick argued that Rawls' suggestion that not only natural talents but also virtues of character are undeserved aspects of ourselves for which we cannot take credit, "can succeed in blocking the introduction of a person's autonomous choices and actions (and their results) only by attributing everything noteworthy about the person completely to certain sorts of 'external' factors. So denigrating a person's autonomy and prime responsibility for his actions is a risky line to take for a theory that otherwise wishes to buttress the dignity and self-respect of autonomous beings."
Nozick's critique has been interpreted in two different ways: The conventional understanding of it is as a libertarian assessment of procedural justice which maintains that while it might be true that peoples' actions are, in whole or in part, determined by factors that are morally arbitrary this is irrelevant to assignments of distributive shares. The reason for this is that individuals are self-owners with inviolable rights in their bodies and talents, and they have the freedom to take advantage of these regardless of whether the self-owned properties are theirs for reasons that are morally arbitrary or not.
Another, more unconventional interpretation of Nozick's critique is represented by Jean Hampton. She points out that there seems to be a subterranean assumption in Nozick's rejection of Rawls' account of natural endowments as collective assets. This assumption is the idea that the choices individuals make regarding how they will use their labour and their property are ones for which they should be held responsible. People who do not work hard and invest imprudently should be held responsible for those choices and not receive assistance from an egalitarian welfare state. If they do work hard and invest well however, they should also be held responsible for those choices and allowed to reap the benefits from their strivings. Hampton asks the question "whether the ground of Nozick's conception of absolute rights is not only a conception of liberty but also a conception of moral responsibility that is […] closely associated to our notion of liberty."
While Hampton's interpretation of Nozick is unconventional, there are indeed other political philosophers who endorse the position she outlines. Their main observation is that sometimes people who are badly off might be so because of their own irresponsible conduct, and the charge is that theories favouring policies of redistribution of resources from individuals who are better off to those worse off ignore this crucial point, i.e. that people might be unequally deserving on account of their wilful conduct.
Sometimes the claim is that the redistributive systems often favoured by egalitarian political theorists might have disastrous consequences in that they promote sloth, and allow free riding on the productive by the lazy. These arguments are instrumental in their appeal to undeservingness. They refer to the allegedly bad consequences of a redistributive social system and do not necessarily involve any reference to the moral worthiness of those who make greater efforts, wiser investments, and so on.
At other times however, the argument invokes a moral ideal holding desert valuable for its own sake. On this view helping the undeserving, and failing to help the deserving, is deemed intrinsically unfair regardless of further consequences. The charge against Rawls for instance, is that people actually might deserve the gains flowing from their natural endowments, or at least those they achieve by striving conscientiously.