Stephen Law and the Barefoot Bum have both written numerous articles about relativism. The Bum has some particularly interesting thoughts, while Law's debate is intriguing because of the exaggerated poles of debate he seems to be operating with. He sets up what appears to be a phoney dichotomy between Authoritarianism (the belief in one overall moral truth) and Relativistic non-judgementalism (unappealing idea that all moral beliefs are equally convincing) largely borrowed from the religious fundamentalists he seeks to combat. If you find this article interesting I suggest you check out their sites.
There is a prevalent point of view which holds that morality should have some foundation in objective truth and fact. This idea seems to me entirely wrong-headed in that it mischaracterises the nature of moral belief. A scientific theory can be true but morality seems to depend on conventions, emotions and beliefs.
Many religious believers think that morality has foundation in truth because under such systems there seems to be a correct way to live one's life. Such a viewpoint makes sense in that religions have a hugely ritualistic character and there is often an emphasis on correct ways of living. However, this viewpoint depends on the existence of a god. Many people believe the existence of a god improbable and so the dependence of moral truth on such a controversial being is extremely unsatisfactory, at least for those who have not had the Road to Damascus moment.
Law interestingly seems to be a radical atheist and a believer in non-relative moral truth but sadly despite my attempts to press him he did not provide me with an explanation of what he believes these non-relative moral truths are. Professional philosophers are by instinct very careful and so I hope such an account will be forthcoming. I'm sure it will be interesting even if I suspect he will have difficulty convincing myself and many others.
A common example in the literature of a non-relative moral truth is "killing a child for fun is morally wrong". Most of us would assent to this statement and we would be vaguely disturbed by other people we met who believed differently and started recounting how they got their kicks every afternoon. Yet despite the unappealing nature of this statement and the fact I would never want to live in a society that held it true, the idea that it is a non-relative truth seems extremely odd even if it is the kind of attitude we would be extremely proud of holding.
The best way it seems to me to retain sense of moral attitudes is to assert that all our moral beliefs and emotions are interconnected. The strength of our belief that "killing a child for fun is morally wrong" is not undermined by the consciousness that it is dependent on all sorts of other beliefs. We need only consider the proposition transposed to the animal kingdom and we will realise such qualms do not arise in interspecies interaction. The need to communicate and dialogue about morality thus becomes greater when it is realised that there is "no non-relative moral truth" because it concedes that people can be convinced by your beliefs and yet the fact that disagreement arises need be nothing to do with one side being objectively right.
As this is a blog I'd like to continue this discussion later and provide some real arguments for the belief there are no non-relative moral truths. Yet I hope this has provided a rough outline of the issues.