Kegan, Robert. In over Our Heads: The Mental Demands of Modern Life. Cambridge, MA: Harvard University Press, 1994.
The Author – Robert Kegan
Kegan is a professor of Adult Learning at Harvard, specializing in cognitive developmental psychology. He has dedicated his career to studying what he has come to call “the evolving self.” Prior to his quest, which began in the 1980s, the conventional wisdom regarding human cognitive development was that all significant cognitive development ceased in late adolescence. In other words, a person’s ability to change the way they think stops at the onset of adulthood. The only type of change that an adult can expect is technical change. Adults can learn more, but they can’t change the way they learn or perceive the world. Kegan’s research has demonstrated that this is not true. He studied hundreds of people over a number of years and discovered that adults can and do develop—evolve—cognitively beyond adolescence.