The American psychologist Lawrence Kohlberg (1927 - 1987) applied Piaget's epigenetic model of cognitive development to the development of ethics and moral reasoning in children and adults. To determine stages of moral reasoning, Kohlberg used moral dilemmas, that is, short stories that require a moral decision.
From his data, he distilled two preconventional stages: (1) obedience/punishment, and (2) self-interest; two conventional stages: (3) interpersonal accord/conformity, and (4) authority/social order; and two postconventional stages: (5) social contract/human rights, and (6) universal human ethics. Like stages of cognitive development, Kohlberg believed that regression to lower stages was not possible.
In the preconventional stages, morality was highly egocentric and based on an action's consequences. In the obedience/punishment stage (1), individuals focused on the direct consequences that their actions. Actions were judged to be morally wrong if the person who committed them was punished. Morality was defined as obeying rules and avoiding negative consequences. The actions of parents or parent substitutes determined moral law. There was no recognition of the others' points of view.
In the stage of self-interest (2), one's own best interest defines what is moral and good. The interests of others are taken into consideration in so far as how they might affect one's own interests.
In the conventional stages, morality is determined by comparing one's actions with societal norms and social expectations. Most adolescents and adults function at this level. In the stage of interpersonal accord/conformity (3), individuals possess an understanding of what others expect from them in terms of fulfilling a social role. Being good is valued. Additionally, there is an appreciation of how one's actions affect interpersonal relationships. One's intentions are taken into consideration.
In the stage of authority/social order (4), the individual feels a duty to obey laws, rules, and social conventions. Laws are valued because they maintain society. Obligations and expectations should be met and fulfilled. A particular idea or ideal may be seen as the basis of right and wrong.
In the postconventional stages, the individual recognizes the value of the individual as opposed to the good of society. The person values his or her own perspective above society's laws and regulations. This disregard of social morality can be mistaken for preconventional morality.
In the stage of social contract/human rights (5), there is a recognition of differing values, opinions, and mores. Laws are seen as social contracts instead of as absolute, rigid entities that have their own, independent existence. They vary from group to group, from place to place, and from time to time. As social contracts, laws are determined through compromise and majority decision. Laws should bring about the greatest good for the most people.
In the stage of universal human ethics (6), morality is based on abstract reasoning. The person is capable of understanding and judging his or her personal rules and beliefs. He or she can understand both his or her actions and those of others in terms of universal ethical principles. He or she is quite capable of taking others' perspectives. What is right and wrong depend on the surrounding circumstances. Laws are valid to the degree that they reflect justice. One is obligated to disobey unjust laws.
Kohlberg noticed certain inconsistencies in the data which led him to propose the possibility of intermediate stages or substages. In particular, there were many individuals who functioned morally between the 4th and 5th stages. Individuals at this sub-stage display considerable annoyance with arbitrary nature of laws and mores.
Kohlberg also recognized that a few individuals seemed to be functioning in a seventh stage. Kohlberg suggested that this seventh stage, which he referred to as transcendental morality (7) and as the morality of cosmic orientation, might combine moral reasoning with religion.