The author complains that the many theoretical classifications, old and new, whatever their merits, have never been tested by application to the instinctual manifestations of the individual. Freud's division of the

instincts into (a) sexual, and (b) ego, is based on psychological investigations; it coincides with their biological distinction. Psycho-analysis has resolved many of the instincts still regarded as primary into their elements, and has studied the inter-relationship and fate of these elements. Jones proposes as a working scheme a division of all instinctual manifestations into those of attraction and repulsion. The first would include hunger and sexuality, and in the second group (all ego manifestations) are placed aversion, flight, and hostility.