By Cyril Burt.

“There is an old tripartite division of the mind, which dis-tinguishes, as relatively independent aspects of our common conscious life, intelligence, emotion, and character. It views a human being as one who knows, and feels, and wills. In considering, therefore, children whose minds are subnormal, it becomes convenient to recognize three classes or types: first, those who are subnormal intellectually; secondly, those who are subnormal emotionally; and, thirdly, those who are subnormal in morality and character—or, in single words, the backward, the unstable, and the delinquent.”

New York: D. Appleton, 1930.619p.