Although the idea that one should do what can reasonably be expected to have the best consequences is obviously attractive, consequentialism is open to several objections. As mentioned earlier, one difficulty is that some of the implications of consequentialism clash with settled moral convictions. Consequentialists, it is said, disregard the Kantian principle of treating human beings as ends in themselves. It is also claimed that, because consequentialists must always aim at the good, impartially conceived, they cannot place adequate value on—or even enter into—the most basic human relationships, such as love and friendship, because these relationships require that one be partial to certain other people, preferring their interests to those of strangers. Related to this objection is the claim that consequentialism is too demanding, for it seems to insist that people constantly compare their most innocent activities with other actions they might perform, some of which—such as fighting world poverty—might lead to a greater good, impartially considered. Another objection is that the calculations that consequentialism demands are too complicated to make, especially if—as in many but not all versions of consequentialism—they require one to compare the happiness or preferences of many different people.

Consequentialists defended themselves against these objections in various ways. Some resorted to rule-consequentialism or to a two-level view like Hare’s. Others acknowledged that consequentialism is inconsistent with many widely accepted moral convictions but did not regard this fact as a good reason for rejecting the basic position. A hard-line consequentialist, for example, may argue that the inconsistency is less important than it may seem, because the situations in which it would arise are unlikely ever to occur—e.g., the situation in which one may save the lives of several innocent human beings by killing one innocent human being (in order for this example to count against the consequentialist, one must assume that the killing of the innocent person produces no significant negative consequences other than the death itself). As to the objection that consequentialism is too demanding, some consequentialists simply replied that acting morally is not always an easy thing to do. The difficulty of making interpersonal comparisons of utility was generally acknowledged, but it was also noted that the inexact nature of such comparisons does not prevent people from making them every day, as when a group of friends decides which movie they will see together.

An ethics of prima facie duties

In the first third of the 20th century, the chief alternative to utilitarianism was provided by the intuitionists, especially W.D. Ross. Because of this situation, Ross’s normative position was often called “intuitionism,” though it would be more accurate and less confusing to reserve this term for his metaethical view (which, incidentally, was also held by Sidgwick) and to refer to his normative position by the more descriptive label, an “ethics of prima facie duties.”

Ross’s normative ethics consisted of a list of duties, each of which is to be given independent weight: fidelity, reparation, gratitude, beneficence, nonmaleficence, and self-improvement. If an act is in accord with one and only one of these duties, it ought to be carried out. Often, of course, an act will be in accord with two or more duties; e.g., one may respect the duty of gratitude by lending money to a person from whom one once received help, or one may respect the duty of beneficence by loaning the money to others, who happen to be in greater need. This is why the duties are, Ross says, “prima facie” rather than absolute; each duty can be overridden if it conflicts with a more stringent duty.

An ethics structured in this manner may match ordinary moral judgments more closely than a consequentialist ethic, but it suffers from two serious drawbacks. First, how can one be sure that just those duties listed by Ross are independent sources of moral obligation? Ross could respond only that if one examines them closely one will find that these, and these alone, are self-evident. But other philosophers, even other intuitionists, have found that what was self-evident to Ross was not self-evident to them. Second, even if Ross’s list of independent prima facie moral duties is granted, it is still not clear how one is to decide, in a particular situation, when a less-stringent duty should be overridden by a more stringent one. Here, too, Ross had no better answer than an unsatisfactory appeal to intuition.

Rawls’s theory of justice

When philosophers again began to take an interest in normative ethics in the 1960s, no theory could rival utilitarianism as a plausible and systematic basis for moral judgments in all circumstances. Yet, many philosophers found themselves unable to accept utilitarianism. One common ground for dissatisfaction was that utilitarianism does not offer any principle of justice beyond the basic idea that everyone’s happiness—or preferences, depending on the form of utilitarianism—counts equally. Such a principle is quite compatible with sacrificing the welfare of a few to the greater welfare of the many—hence the enthusiastic welcome accorded to Rawls’s A Theory of Justice when it appeared in 1971. Rawls offered an alternative to utilitarianism that came close to its rival as a systematic theory of what one ought to do; at the same time, it led to conclusions about justice very different from those of the utilitarians.

Rawls asserted that if people had to choose principles of justice from behind a veil of ignorance that restricted what they could know of their own positions in society, they would not choose principles designed to maximize overall utility, because this goal might be attained by sacrificing the rights and interests of groups that they themselves belong to. Instead, they would safeguard themselves against the worst possible outcome, first, by insisting on the maximum amount of liberty compatible with the same liberty for others, and, second, by requiring that any redistribution of wealth and other social goods is justified only if it improves the position of those who are worst-off. This second principle is known as the “maximin” principle, because it seeks to maximize the welfare of those at the minimum level of society. Such a principle might be thought to lead directly to an insistence on the equal distribution of goods, but Rawls pointed out that, if one accepts certain assumptions about the effect of incentives and the benefits that may flow to all from the productive labours of the most talented members of society, the maximin principle is consistent with a considerable degree of inequality.

In the decade following its appearance, A Theory of Justice was subjected to unprecedented scrutiny by moral philosophers throughout the world. Two major questions emerged: Were the two principles of justice soundly derived from the original contract situation? And did the two principles amount, in themselves, to an acceptable theory of justice?

To the first question, the general verdict was negative. Without appealing to specific psychological assumptions about an aversion to risk—and Rawls disclaimed any such assumptions—there was no convincing way in which Rawls could exclude the possibility that the parties to the original contract would choose to maximize average, rather than overall, utility and thus give themselves the best-possible chance of having a high level of welfare. True, each individual making such a choice would have to accept the possibility that he would end up with a very low level of welfare, but that might be a risk worth taking for the sake of a chance at a very high level.

Even if the two principles cannot be validly derived from the original contract, they might be sufficiently attractive to stand on their own. Maximin, in particular, proved to be a popular principle in a variety of disciplines, including welfare economics, a field in which preference utilitarianism had earlier reigned unchallenged. But maximin also had its critics; one of the charges leveled against it was that it could require a society to forgo very great benefits to the vast majority if, for some reason, they would entail some loss, no matter how trivial, to those who are the worst-off.

Rights theories

Although appeals to rights have been common since the great 18th-century declarations of the rights of man (see Declaration of the Rights of Man and of the Citizen; Declaration of Independence), most ethical theorists have treated rights as something that must be derived from more basic ethical principles or else from accepted social and legal practices. However, beginning in the late 20th century, especially in the United States, rights were commonly appealed to as a fundamental moral principle. Anarchy, State, and Utopia (1974), by the American philosopher Robert Nozick (1938–2002), is an example of such a rights-based theory, though it is mostly concerned with applications in the political sphere and says very little about other areas of normative ethics. Unlike Rawls, who for all his disagreement with utilitarianism was still a consequentialist of sorts, Nozick was a deontologist. The rights to life, liberty, and legitimately acquired property are absolute, he insists; no act that violates them can be justified, no matter what the circumstances or the consequences. Nozick also held that one has no duty to help those in need, no matter how badly off they may be, provided that their neediness is not one’s fault. Thus, governments may appeal to the generosity of the rich, but they may not tax them against their will in order to provide relief for the poor.

The American philosopher Ronald Dworkin argued for a different view in Taking Rights Seriously (1977) and subsequent works. Dworkin agreed with Nozick that rights should not be overridden for the sake of improved welfare: rights are, he said, “trumps” over ordinary consequentialist considerations. In Dworkin’s theory, however, the rights to equal concern and respect are fundamental, and observing these rights may require one to assist others in need. Accordingly, Dworkin’s view obliges the state to intervene in many areas to ensure that rights are respected.

In its emphasis on equal concern and respect, Dworkin’s theory was part of a late 20th-century revival of interest in Kant’s principle of respect for persons. This principle, like the value of justice, was often said to be ignored by utilitarians. Rawls invoked Kant’s principle when setting out the underlying rationale of his theory of justice. The principle, however, suffers from a certain vagueness, and attempts to develop it into something more specific that could serve as the basis of a complete ethical theory have not been wholly successful.