Moral relativism is more easily understood in comparison to moral absolutism. Absolutism claims that morality relies on universal principles (natural law, conscience). Christian absolutists believe that God is the ultimate source of our common morality, and that it is, therefore, as unchanging as He is. Moral relativism asserts that morality is not based on any absolute standard. Rather, ethical “truths” depend on variables such as the situation, culture, one's feelings, etc.
Several things can be said of the arguments for moral relativism which demonstrate their dubious nature. First, while many of the arguments used in the attempt to support relativism might sound good at first, there is a logical contradiction inherent in all of them because they all propose the “right” moral scheme—the one we all ought to follow. But this itself is absolutism. Second, even so-called relativists reject relativism in most cases. They would not say that a murderer or rapist is free from guilt so long as he did not violate his own standards.
Relativists may argue that different values among different cultures show that morals are relative to different people. But this argument confuses the actions of individuals (what they do) with absolute standards (whether they should do it). If culture determines right and wrong, how could we have judged the Nazis? After all, they were only following their culture's morality. Only if murder is universally wrong were the Nazis wrong. The fact that they had “their morality” does not change that. Further, although many people have different practices of morality, they still share a common morality. For instance, abortionists and anti-abortionists agree that murder is wrong, but they disagree on whether abortion is murder. So, even here, absolute universal morality is shown to be true.
Some claim that changing situations make for changing morality—in different situations different acts are called for that might not be right in other situations. But there are three things by which we must judge an act: the situation, the act, and the intention. For example, we can convict someone of attempted murder (intent) even if they fail (act). So situations are part of the moral decision, for they set the context for choosing the specific moral act (the application of universal principles).
The main argument relativists appeal to is that of tolerance. They claim that telling someone their morality is wrong is intolerant, and relativism tolerates all views. But this is misleading. First of all, evil should never be tolerated. Should we tolerate a rapist's view that women are objects of gratification to be abused? Second, it is self-defeating because relativists do not tolerate intolerance or absolutism. Third, relativism cannot explain why anyone should be tolerant in the first place. The very fact that we should tolerate people (even when we disagree) is based on the absolute moral rule that we should always treat people fairly—but that is absolutism again! In fact, without universal moral principles there can be no goodness.
The fact is that all people are born with a conscience, and we all instinctively know when we have been wronged or when we have wronged others. We act as though we expect others to recognize this as well. Even as children we knew the difference between “fair” and “unfair.” It takes bad philosophy to convince us that we are wrong and that moral relativism is true.