In what area did Kohlberg conduct influential research?

Lawrence Kohlberg conducted influential research primarily in the area of moral development and reasoning. His most notable contribution is the development of a stage theory of moral development, which outlines the progression of moral reasoning in children and adults. Kohlberg proposed that individuals move through different levels of moral understanding, which he categorized into three main levels: pre-conventional, conventional, and post-conventional. Each level includes two stages that reflect increasingly complex and abstract ways of thinking about morality.

Kohlberg's research emphasized how moral reasoning evolves as individuals grow cognitively and socially, illustrating the relationship between cognitive development and moral understanding. His work built on and extended Jean Piaget's theories, demonstrating that moral reasoning is not static but develops over time through a series of stages that correspond to a person's cognitive development and ethical understanding. This significant contribution has had lasting implications in educational psychology, developmental psychology, and ethical theory.