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by published, updated 2013


Lawrence Kohlberg (1958) agreed with Piaget's (1932) theory of moral development in principle but wanted to develop his ideas further. 

He used Piaget’s storytelling technique to tell people stories involving moral dilemmas.  In each case he presented a choice to be considered, for example, between the rights of some authority and the needs of some deserving individual who is being unfairly treated.

One of the best known of Kohlberg’s (1958) stories concerns a man called Heinz who lived somewhere in Europe.

Heinz’s wife was dying from a particular type of cancer. Doctors said a new drug might save her. The drug had been discovered by a local chemist and the Heinz tried desperately to buy some, but the chemist was charging ten times the money it cost to make the drug and this was much more than the Heinz could afford.

Heinz could only raise half the money, even after help from family and friends. He explained to the chemist that his wife was dying and asked if he could have the drug cheaper or pay the rest of the money later.

The chemist refused, saying that he had discovered the drug and was going to make money from it. The husband was desperate to save his wife, so later that night he broke into the chemist’s and stole the drug.

Kohlberg asked a series of questions such as:

1. Should Heinz have stolen the drug?
2. Would it change anything if Heinz did not love his wife?
3. What if the person dying was a stranger, would it make any difference?
4. Should the police arrest the chemist for murder if the woman died?

By studying the answers from children of different ages to these questions Kohlberg hoped to discover the ways in which moral reasoning changed as people grew older. The sample comprised 72 Chicago boys aged 10–16 years, 58 of whom were followed up at three-yearly intervals for 20 years (Kohlberg, 1984).

Each boy was given a 2-hour interview based on the ten dilemmas. What Kohlberg was mainly interested in was not whether the boys judged the action right or wrong, but the reasons given for the decision. He found that these reasons tended to change as the children got older.

He identified three distinct levels of moral reasoning each with two sub stages. People can only pass through these levels in the order listed. Each new stage replaces the reasoning typical of the earlier stage. Not everyone achieves all the stages.

Kohlberg's Stages of Moral Development

Level 1 - Pre-conventional morality

At the pre-conventional level (most nine-year-olds and younger, some over nine), we don’t have a personal code of morality. Instead, our moral code is shaped by the standards of adults and the consequences of following or breaking their rules.

Authority is outside the individual and reasoning is based on the physical consequences of actions.

Stage 1. Obedience and Punishment Orientation. The child/individual is good in order to avoid being punished. If a person is punished, they must have done wrong.

Stage 2. Individualism and Exchange. At this stage children recognize that there is not just one right view that is handed down by the authorities. Different individuals have different viewpoints.

Level 2 - Conventional morality

At the conventional level (most adolescents and adults), we begin to internalize the moral standards of valued adult role models.

Authority is internalized but not questioned and reasoning is based on the norms of the group to which the person belongs.

Stage 3. Good Interpersonal Relationships. The child/individual is good in order to be seen as being a good person by others. Therefore, answers relate to the approval of others.

Stage 4. Maintaining the Social Order. The child/individual becomes aware of the wider rules of society so judgments concern obeying the rules in order to uphold the law and to avoid guilt.

Level 3 - Post-conventional morality

Individual judgment is based on self-chosen principles, and moral reasoning is based on individual rights and justice. According to Kohlberg this level of moral reasoning is as far as most people get.

Only 10-15% are capable of the kind of abstract thinking necessary for stage 5 or 6 (post-conventional morality). That is to say most people take their moral views from those around them and only a minority think through ethical principles for themselves.

Stage 5. Social Contract and Individual Rights. The child/individual becomes aware that while rules/laws might exist for the good of the greatest number, there are times when they will work against the interest of particular individuals. 

The issues are not always clear cut. For example, in Heinz’s dilemma the protection of life is more important than breaking the law against stealing.

Stage 6. Universal Principles. People at this stage have developed their own set of moral guidelines which may or may not fit the law. The principles apply to everyone.

E.g. human rights, justice and equality. The person will be prepared to act to defend these principles even if it means going against the rest of society in the process and having to pay the consequences of disapproval and or imprisonment. Kohlberg doubted few people reached this stage.

Problems with Kohlberg's Methods

1. The dilemmas are artificial (i.e. they lack ecological validity)

Most of the dilemmas are unfamiliar to most people (Rosen, 1980). For example, it is all very well in the Heinz dilemma asking subjects whether Heinz should steal the drug to save his wife.

However Kohlberg’s subjects were aged between 10 and 16. They have never been married, and never been placed in a situation remotely like the one in the story. How should they know whether Heinz should steal the drug?

2. The sample is biased

According to Gilligan (1977), because Kohlberg’s theory was based on an all-male sample, the stages reflect a male definition of morality (it’s androcentric). Mens' morality is based on abstract principles of law and justice, while womens' is based on principles of compassion and care.

Further, the gender bias issue raised by Gilligan is a reminded of the significant gender debate still present in psychology, which when ignored, can have a large impact on the results obtained through psychological research.

3. The dilemmas are hypothetical (i.e. they are not real)

In a real situation, what course of action a person takes will have real consequences – and sometimes very unpleasant ones for themselves. Would subjects reason in the same way if they were placed in a real situation? We just don’t know.

The fact that Kohlberg’s theory is heavily dependent on an individual’s response to an artificial dilemma brings question to the validity of the results obtained through this research.  People may respond very differently to real life situations that they find themselves in than they do with an artificial dilemma presented to them in the comfort of a research environment.

4. Poor research design

The way in which Kohlberg carried out his research when constructing this theory may not have been the best way to test whether all children follow the same sequence of stage progression. His research was cross-sectional, meaning that he interviewed children of different ages to see what level of moral development they were at. 

A better way to see if all children follow the same order through the stages would have been to carry out longitudinal research on the same children.

However, longitudinal research on Kohlberg’s theory has since been carried out by Colby et al. (1983) who tested 58 male participants of Kohlberg’s original study. She tested them 6 times in the span of 27 years and found support for Kohlberg’s original conclusion, that we all pass through the stages of moral development in the same order.

Problems with Kohlberg's Theory

1. Are there distinct stages of moral development?

Kohlberg claims that there are but the evidence does not always support this conclusion. For example a person who justified a decision on the basis of principled reasoning in one situation (post conventional morality stage 5 or 6) would frequently fall back on conventional reasoning (stage 3 or 4) with another story. In practice it seems that reasoning about right and wrong depends more upon the situation than upon general rules.

What is more individuals do not always progress through the stages and Rest (1979) found that one in fourteen actually slipped backwards. The evidence for distinct stages of moral development looks very weak and some would argue that behind the theory is a culturally biased belief in the superiority of American values over those of other cultures and societies.

2. Does moral judgement match moral behavior?

Kohlberg never claimed that there would be a one to one correspondence between thinking and acting (what we say and what we do) but he does suggest that the two are linked. However, Bee (1994) suggests that we also need to take account of:

    a) habits that people have developed over time.

    b) whether people see situations as demanding their participation.

    c) the costs and benefits of behaving in a particular way.

    d) competing motive such as peer pressure, self interest and so on.

Overall Bee points out that moral behavior is only partly a question of moral reasoning. It is also to do with social factors.

3. Is justice the most fundamental moral principle?

This is Kohlberg’s view. However, Gilligan (1977) suggests that the principle of caring for others is equally important. Furthermore Kohlberg claims that the moral reasoning of males has been often in advance of that of females.

Girls are often found to be at stage 3 in Kohlberg’s system (good boy-nice girl orientation) whereas boys are more often found to be at stage 4 (Law and Order orientation). Gilligan replies:

“The very traits that have traditionally defined the goodness of women, their care for and sensitivity to the needs of others, are those that mark them out as deficient in moral development.”

In other words Gilligan is claiming that there is a sex bias in Kohlberg’s theory. He neglects the feminine voice of compassion, love and non-violence, which is associated with the socialization of girls.

Gilligan reached the conclusion that Kohlberg’s theory did not account for the fact that women approach moral problems from an ‘ethics of care’, rather than an ‘ethics of justice’ perspective, which challenges some of the fundamental assumptions of Kohlberg’s theory.


Bee, H. L. (1994). Lifespan development. HarperCollins College Publishers.

Colby, A., Kohlberg, L., Gibbs, J., & Lieberman, M. (1983). A longitudinal study of moral judgment. Monographs of the Society for Research in Child Development, 48 (1-2, Serial No. 200). Chicago: University of Chicago Press.

Gilligan, C. (1977). In a different voice: Women's conceptions of self and of morality. Harvard Educational Review, 47(4), 481-517.

Kohlberg, L. (1958). The Development of Modes of Thinking and Choices in Years 10 to 16. Ph. D. Dissertation, University of Chicago.

Kohlberg, L. (1984). The Psychology of Moral Development: The Nature and Validity of Moral Stages (Essays on Moral Development, Volume 2). Harper & Row

Piaget, J. (1932). The moral judgment of the child. London: Kegan Paul, Trench, Trubner & Co.

Rest, J. R. (1979). Development in judging moral issues. University of Minnesota Press.

Rosen, B. (1980). Moral dilemmas and their treatment. In, Moral development, moral education, and Kohlberg. B. Munsey (Ed). (1980), pp. 232-263. Birmingham, Alabama: Religious Education Press.

How to cite this article:

McLeod, S. A. (2013). Kohlberg. Retrieved from

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