It is the position that moral or ethical positions do not reflect objective and/or universal moral truths, but instead make claims relative to social, cultural, historical or personal circumstances. It does not deny outright the truth-value or justification of moral statements but affirms relative forms of them. It may be described by the common saying: “When in Rome, do as the Romans do”.
Moral Relativists point out that humans are not omniscient, and history is replete with examples of individuals and societies acting in the name of an infallible truth later demonstrated to be more than fallible, so we should be very wary of basing important ethical decisions on a supposed absolute claim. Absolutes also tend to inhibit experimentation and foreclose possible fields of inquiry which might lead to progress in many fields, as well as stifling the human spirit and quest for meaning. In addition, the short term proves itself vastly superior in the ethical decision-making process than the relatively unknown long-term.
Relativistic positions may specifically see moral values as applicable only within certain cultural boundaries (Cultural Relativism) or in the context of individual preferences. A related but slightly different concept is that of Moral Pluralism (or Value Pluralism), the idea that there are several values which may be equally correct and fundamental, and yet in conflict with each other (e.g. the moral life of a nun is incompatible with that of a mother, yet there is no purely rational measure of which is preferable).
An extreme relativist position might suggest that judging the moral or ethical judgments or acts of another person or group has no meaning at all, though most relativists propound a more limited version of the theory.
Moral Relativism generally stands in contrast to Moral Absolutism, Moral Universalism.