By an 'absolute' value or good is meant one that maintains its validity under any and every circumstance, no matter what. For example the ancient maxim of the Stoics 'Let justice be done though the heavens fall' is a dramatic way of expressing the absolute validity of justice as a principle. With the moral theologians of the Middle Ages, the general principle 'Follow the good and avoid the evil' was regarded as a major or ultimate premise carrying with it absolute validity. In more modern philosophy the ethics of Immanuel Kant furnishes the best example of an ethical absolute. Good will, which Kant defined as the will that acts out of respect for the moral law, has absolute validity; it is good in any context and has a worth that cannot be calculated because it surpasses all values in exchange.

Ethical absolutes come under attack from at least three distinct points of view. From the point of view of some forms of subjectivism in ethics there can be no absolutes because moral judgements have neither objectivity nor universality and there is not sufficient constancy in human nature to guarantee for any good or value a place of absolute validity. It is useful to notice that not all forms of subjectivism are thus relativistic, but only those positions according to which human nature has no universal structure. The second and more powerful source of relativism in ethics stems from anthropological and cultural analyses that make paramount the great variety of customs and practices to be found in different cultures. From this point of view, ethical absoulutes are ruled out because there cannot possibly be a universal agreement or consensus of opinion with regard to any standard or norm. Each set of values is 'relative' to a geographical time and place and we have no way of transcending this situation and of establishing any one set of norms as the final criterion.

Ethical absolutes have also been attacked from a third source, this time in the name of a religious standpoint. Kierkegaard, for example, in his famous 'teleological suspension of the ethical' was calling attention to the problems that arise when the ethical standpoint is absolutized and becomes free of any critical vantage point beyond itself. If the ethical becomes absolute then legalism and moralism result. The ethical must be limited by the mercy and forgiveness of the religious and if it is not, the ethical will absolutize itself with evil consequences. A similar point about absoluitizing the ethical is made from the standpoint of dialectical theology so-called; the counsels of perfection stemming from the teaching of Jesus are not meant to apply absolutely and literally to the world of actual existence but rather are said to define the ideal standard in terms of which humanity and the world are judged. As absolute, the Christian ethic is said to be an 'impossible ideal,' and yet it retains its relevance for historical life.