How do universal moral rules challenge ethical relativism?

Ethical relativism is the doctrine that there are no absolute moral truths and that right and wrong vary by individual or society. The existence of universal moral rules challenges this view by suggesting that certain standards transcend cultural boundaries.12

Critics of ethical relativism argue that the theory fails to account for the common ground observed across human societies. Anthropologists have noted that virtually all cultures share fundamental values necessary for social existence, such as prohibitions against murder and requirements for truthfulness. These commonalities suggest that morality may not be entirely arbitrary or merely a product of local custom.12

However, the existence of these universal rules does not automatically disprove ethical relativism. Philosophers point out that even if a rule is universally practiced, it does not necessarily make it objectively "right". For example, if all societies practiced slavery, it would not prove that slavery is morally acceptable. Furthermore, some argue that universal practices may simply be evolutionary adaptations that are advantageous for survival, rather than objective moral truths. Ultimately, the debate remains a central theme in ethics, as it questions whether an objective, rationally justifiable moral code exists or if morality is fundamentally relative.32