Cultural Relativism suggests that each person's culture is the norm or standard by which we determine what our morals or behavioral actions will take. Essentially relativism rejects the notion that there are absolutes that govern our behavior. How then do we determine how we behave, and how reasonable and plausible is this position?
This complex question crosses the fields between personal morality and social ethics. According to such thinkers as Emile Durkheim, the society with which we associate (on the large scale, our citizenship or our race or our family; on a smaller scale, our economic group, our gang, our immediate circle of friends, etc.) has determined, through its history, a set of acceptable behaviors, and by extension a set of unacceptable behaviors. When we base our actions on those criteria, we are acting “ethically” or “unethically.” But when we base our behavior on personal values (Golden Rule, cause/effect, aesthetics, etc.), we may violate the social boundaries (such people are sometimes referred to as “outliers). To take an innocuous example, body tattoos may be socially acceptable or unacceptable, depending on society, history, even economic status, but one’s personal morality is not involved – if you want a tattoo, you get one. Another example might be the “ethics” of law enforcement vs. the Biblical caveat against taking a life. We determine our “right” actions, then, by balancing our personal morality with our social “ethics”. For the modern thinker, determining how we behave is independent of some universal “law.”