It is apparent that the importance of the limbic system is essentially for survival. The inability to discriminate enemy from friend as well as loss of the proper affective response to what is dangerous or safe to the organism may be thought of as more central to survival than what is described as "other higher intellectual functions." The case described is a dramatic expression of such a transient limbic dementia originally described by Klüver and Bucy in their syndrome. Since Klüver and Bucy originally described their syndrome, the structural and functional understanding of the limbic system has been greatly increased. Although a rare occurrence in man, the Klüver-Bucy syndrome serves as a demonstration of an unusual brain syndrome whose theoretical and experimental basis has been greatly enlarged since first described.