Lawrence Kohlberg

An American psychologist whose work centered in the area of the development of moral reasoning.

Lawrence Kohlberg was born in Bronxville, New York, and after serving in the Merchant Marine during World War II, received his B.A. (1948) and Ph.D. (1958) from the University of Chicago. He served as an assistant professor at Yale University from 1959 to 1961 and was a fellow of the Center of Advanced Study of Behavioral Science in 1962. Kohlberg began teaching at the University of Chicago in 1963, where he remained until his 1967 appointment to the faculty of Harvard University, where he has served as professor of education and social psychology. Kohlberg is best known for his work in the development of moral reasoning in children and adolescents. Seeking to expand on Jean Piaget's work in cognitive development and to determine whether there are universal stages in moral development as well, Kohlberg conducted a long-term study in which he recorded the responses of boys aged seven through adolescence to hypothetical dilemmas requiring a moral choice. The most famous sample dilemma is whether the husband of a critically ill woman is justified in stealing a drug that could save her life if the pharmacist is charging much more than he can afford to pay. Based on the results of his study, Kohlberg concluded that children and adults progress through six stages in the development of moral reasoning. He also concluded that moral development is directly related to cognitive development, with older children able to base their responses on increasingly broad and abstract ethical standards.

In evaluating his research, Kohlberg was primarily interested not in the children's responses themselves, but in the reasoning behind them. Based on their thought processes, he discerned a gradual evolution from self-interest to principled behavior and developed a chronological scheme of moral development consisting of three levels, each made up of two separate stages. Each stage involved increasingly complex thought patterns, and as children arrive at a given stage, they tend to consider the basis for previous judgments as invalid.

Children from the ages of seven through ten act on the pre-conventional level. At this level, they defer to adults and obey rules based on the immediate consequences of their actions. The behavior of children at this level is essentially pre-moral. At Stage 1, they obey rules in order to avoid punishment, while at Stage 2 their behavior is mostly motivated by the desire to obtain rewards.

Starting at around age ten, children enter the conventional level, where their behavior is guided by the opinions of other people and the desire to conform. At Stage 3, the emphasis is on being a “good boy” or “good girl” in order to win approval and avoid disapproval, while at Stage 4 the concept of doing one's duty and upholding the social order becomes predominant. At this stage, respecting and obeying authority (of parents, teachers, God) is an end in itself, without reference to higher principles. By the age of 13, most moral questions are resolved on the conventional level.

Progress through the different stages depends upon the type of thinking that a child or adolescent is capable of at a given point, and also on the negotiation of previous stages. Kohlberg points out that many people never pass beyond the conventional level, and that the most clearly principled response at Stage 6 was expressed by fewer than 10% of adolescents over the age of 16. (In relation to the dilemma of the stolen drug, such a response would clearly articulate the existence of a moral law that transcends society's laws about stealing and the sanctity of human life over financial gain.)

Kohlberg's system is closely related to Piaget's theories, both in its emphasis on cognitive development and in its designation of a chronological series of stages, each dependent on the preceding ones. It also has important implications for the nature-nurture controversy, as it stresses the role of innate, rather than environmental, factors in moral development. According to Kohlberg, progress from one level or stage to the next involves an internal cognitive reorganization that is more complex than a mere acquisition of precepts from peers, parents, and other authorities.

Critics of Kohlberg's work point out that he interviewed only boys and suggest that moral development for girls may follow a different course. They also point out that some of the hypothetical dilemmas may be unfamiliar to children at certain ages. For example, in the dilemma involving a critically ill wife and theft of a drug, young children are familiar with the concept of theft, but they have no concept of marital love and responsibility.

Kohlberg's most famous book is The Philosophy of Moral Development: Moral Stages and the Idea of Justice, the first volume in a series entitled Essays on Moral Development. The second volume, The Psychology of Moral Development, was published in 1984.

See also Cognitive development .



Kohlberg, Lawrence. The Philosophy ofMoral Development: Moral Stages and the Idea of Justice. San Francisco: Harper & Row, 1981.

Kohlberg, Lawrence. The Psychology of Moral Development: The Nature and Validity of Moral Stages. San Francisco: Harper & Row, 1984.

Power, F. Clark. Lawrence Kohlberg's Approach to Moral Education. New York: Columbia University Press, 1989.


Beauchamp, Anne. “Lawrence Kohlberg.” (accessed July 30, 2015).

McLeod, Saul. “Kohlberg.” Simply Psychology. (accessed July 30, 2015).