The straw man version of moral relativism is “just do whatever you feel like doing.” But if straw men were the real deal, then we wouldn’t be bothering with such obvious losers as Darwin and Einstein. What I’m about to describe is one version of moral relativism (mine, which is as it should be, given the nature of the subject), and some notions about implications.
I’ll start with the concept of “personal good.” I would hope that this is not controversial (dream on), since it is easily verified and exists in the language in such phrases as cuo bono (“who benefits”), and “whose ox is being gored.” Simply put, one’s notion of what is good or bad is often purely individual. If I am hungry, a can of peanuts is good, because I can eat them and satisfy my hunger. However, for someone with a peanut allergy, peanuts are bad, because if they eat peanuts they could die.
As an aside, let me note that poisons are often called “vile” or “evil,” (similar words with possibly differing roots). This tends toward personification, ascribing human attributes to inanimate matter. The personification may be showing something important. While Hurricane Katrina killed more people than the Oklahoma City bombing, one rarely hears the hurricane itself called evil, not like (for example) illegal drugs are called evil. I’ll suggest that there is a tendency to ascribe “evilness” to things that deceive. A poison may lurk in a tasty food, so it is evil. A drug may convey pleasure, but corrode the spirit, also evil. And so forth. In any case, I’ll argue that the concept of “evil” carries with it an assumed human content, which may be important, given that we are talking about the difference between subjective and objective.
Good and bad are, therefore, at least at one level of discourse, subjective phenomena. Their attribution depends upon a point of view. However, human beings tend to try to objectify their subjective experiences, and the impulse is reasonable, assuming that there is an objective reality, and I’m not here to dispute that. The question here is, “Can one objectify the concepts of good and bad to the point where they become absolute?” This constitutes no problem for religion; morality then becomes a matter of divine judgment as determined by revelation and adherence is a matter of faith. However, this is an assertion rather than an argument and I’ll not deal with it here.
The strongest argument against the idea of purely objective, logically derived, absolute morality is that a number of Very Smart People have tried to devise such a system and have failed. Kant’s Categorical Imperative, for example, leads to the result that one must always be truthful, and so must tell Nazis where the Jews are hidden if they ask. John Rawls’ “A Theory of Justice” contains an interesting thought experiment (What society would you design if you knew you would be a member of it, but could not chose which role you would have?), but it is vulnerable to the inclusion/exclusion problem. Are we only talking about human beings? How about domestic animals? Wild animals? Trees? And if it is only human roles, what do you do about someone who denies the humanity of slaves, the vegetative, the French, fetuses, or terrorists? In any case, any attempt to design a society ab initio is suspect.
(The argument against the Categorical Imperative used above is common in discussions of moral philosophy. It’s often mistaken for “reductio ad absurdum” but the result is more horrific (turning people over to be murdered) than absurd. I’d call it “reductio ad nauseam” but “ad nauseam” is usually taken to mean “massive repetition” and that does not apply, except insofar as this is yet another use of Nazis in an argument, which is seldom a good sign).
The Nazi example is often used as an argument against moral relativism generally, or cultural relativism specifically, but it’s not a fair cop. National Socialism failed on its own terms: it destroyed the German Volk, got its leaders killed, and never achieved anything like its goal of a purified “master race.” That the last goal was impossible should be an indication that “relativism” has real limits, as opposed to the straw man version.
The fundamental principle of morality is that actions have consequences, and some of those consequences are better than others. Moreover, a single action will have multiple consequences, again, with varying value. Even from a solitary point of view that admits no others (the alone-on-a-desert-island example), consequences will vary over time, such that one would need to organize one’s behavior to maximize the good results – over time – and minimize the bad. It does not take much analysis to recognize that, to our hypothetical desert islander, using the morphine in the emergency kit to get high is more likely to have bad consequences than good. Having someone curse someone else’s lack of proper behavior is a good indicator that something has gone wrong in the morals/ethics department, even when the cursee and the curser are the same person with an intervening gap of time.
A philosophy of moral relativism, with its emphasis on point of view, is hardly a prescription for moral laxity or license. In actual fact, it recognizes the difficulties of human action more completely than do absolutist doctrines. Moral absolutism carries within it powerful temptations such as sanctimony and grievance. If some injury is done to me by someone, I consider their actions to be “bad,” which they certainly are, from my point of view. If morals are absolute, then the actions that led to that injury must also be bad, and the people who did them are also bad. If morals are absolute, if they are objective, then it is not necessary for me to consider the point of view of someone who has harmed me. That, after all, is merely their “relative” judgment, while I am backed by an absolute judgment. Add only the doctrine that it is okay to do bad things to bad people (I’m trying to think of some philosophy that does not allow crimes to be punished and I’m not coming up with much), and you have a prescription for war.
In short, absent a deity that speaks in a clear and unambiguous voice, a doctrine of absolute morality appears to be an invitation to projection: making one’s own judgments (and prejudices) the center of the universe, the law which all must obey. Moral relativism, at the very least, carries within it the idea that the moral universe has more than one center. I consider that to be an improvement.