This system asserts that an action is right if one’s culture approves of it. Moral rightness and wrongness are relative to cultures. So, culture A cannot judge culture B by culture A’s moral standards. To each his own.
The subjective relativist believes an action is right if one approves of it himself. If I believe it is right, it is right. This school of thought makes everyone morally infallible as morality is determined by each individual. Genuine moral disagreement between individuals is nearly impossible using this system as moral judgments are a matter of preference (“taste”). It’s bad taste to argue taste.
The universalist asserts that some things are simply right and wrong regardless of culture, geography, religion, or any other qualifiers. For example, the taking of innocent life is wrong no matter where it happens or who does it. It is wrong.
Utilitarianism is a consequentialist theory that weighs outcomes as the greatest measure of morality. If an action produces the greatest possible good, it is morally acceptable. The ends, in other words, justify the means. This system favors effects that have the greatest good for the most people.
The greater good was the underlying theme of a three-film story arc in the Star Trek movies of the 1980s.