Anthropologists in their research into human behavior throughout cultures across all of known human history have revealed the rather dispiriting truth that there is little we can conceive of regarding that behavior, no matter how heinous we might judge the act or the practice, that was not at some time and in some place, sanctioned. Many people today, unwilling to or incapable of embracing a particular worldview and ethical standard such as promulgated by a specific religion, accept the Shakespearean perspective that "there is nothing either good or bad, but thinking makes it so," as articulated by Hamlet. Such persons accept, whether they might express their viewpoint this way precisely or not, a relativist metaphysics that allows no room for universal moral standards. 

If pressed to articulate the relativist view, the average person might reply that no one has a right to impose their moral standards on anyone else, or that various ethical doctrines and teachings can be followed by individuals and by societies alike, with no one opposed to and especially no one condemnatory of a particular set of ethical standards having any valid standing for doing so, and indeed should censured himself or herself for expressing disapproval of any particular set of ethical doctrine or teachings. Defined more formally, ethical relativism is the view that the moral correctness of an act cannot be objectively determined, but depends solely on the moral norms of the society in which the act occurs. That is, particular act A may be justly condemned in society X, but the very same act may be justly practiced in society Y.

The problem with the relativist's view, and it seems a fatal one, is that if no act can be judged right or wrong irrespective of time and place, then there can be no enduring ethical standards at all, and consequently a pervasive skepticism cannot be resisted, and the way is cleared for all the corrosive effects of nihilism.

Is the relativist viewpoint, being, after all, so easily purchased, really a defensible one? The relativist view is a subjectivist one, whereby one holds that moral rules are in some sense a function of opinion or consensus. Certainly Aristotle would disagree, for his concern in the realm of human behavior was human flourishing, or eudaimonia, which can be achieved only by living well, by living a virtuous life. For Aristotle, virtue leads to happiness, the telos of human existence. Aristotle was a not a relativist. Yes he accepted relativity in human existence, for he believed that what constituted courage in one man constituted recklessness in another (e.g., a warrior of a particular size, strength and training engaging in combat a worthy opponent is demonstrating courage, while an older, weaker, untrained individual endeavoring to fight the same opponent demonstrated recklessness), or what was the acceptable amount of food for one individual represented gluttony for another. As many are aware, Aristotle proposed the golden mean as ideal for human flourishing, that, for example, courage is a virtue that is realized between the extremes of cowardice on one end, and recklessness on the other.

As the highly-regarded philosopher Martha Nussbaum explains, Aristotle was not at all a relativist, that in fact he defended an objective conception of ethics, that contrary to the relativist view, there are objective standards that are indispensable to human flourishing. As Nussbaum states, Aristotle held that flourishing is a function of "features of humanness that lie beneath all local traditions" (Non-Relative Virtues: An Aristotelian Approach, 1993). The essential idea here is that particular local traditions can hinder development of virtue, and hence impair human flourishing. For example, Aristotle believed that it is the nature of human beings to seek understanding (Metaphysics), and human flourishing therefore is not attainable in any society in which this desire for understanding was discouraged, or even punished. Given this particular aspect of human beings, there are indeed objective ethical standards, or so Aristotle believed.

The case against the relativist position is being strengthened, rather unexpectedly, not in the philosophy classroom, but in the work of such scientists as the renowned primatologist Frans de Waal, in his studies of non-human primates. He has found what he believes are the building blocks of human ethics in the behavior patterns of these non-human primates, specifically in the discovery of the importance to the cohesion of chimp and bonobo societies of acts of fairness and cooperation, of empathy and consolation. As de Waal points out, living in a society provides survival advantages over solitary existence, and living in a society requires cooperation. One example de Waal offers is the finding that if one chimp grooms another chimp in the morning, then the groomed chimp is more likely to repay the favor through the sharing of its food in the afternoon. His studies of capuchin monkeys reveals that these creatures prize grapes over cucumbers, and that if two monkeys are fed cucumbers equally, all is well, but that is one monkey is fed cucumbers and the other is fed grapes, then the cucumber is no longer seen as satisfactory, and the "cheated" monkey will rattle the cage and even toss away the cucumber. Fairness matters, even to monkeys. 

De Waal is not proposing that these creatures make moral decisions, not in the sense that a human is capable of making a specifically moral decision, but he is making the case that the building blocks of human morality are in evidence in what he documents as the acceptable and the unacceptable behaviors within these primate societies.