The Psychological Birth of the Human Infant. Symbiosis and Individuation: By Margaret S. Mahler, Fred Pine, and Anni Bergman. New York: Basic Books, Inc., 1975. 308 pp.

In this book, a study of normal babies and their mothers, Margaret Mahler and her collaborators substantiate the hypotheses she developed in her earlier studies on infantile psychotic syndromes: 'the universality of the symbiotic origin of the human condition, as well as the hypothesis of an obligatory separation-individuation process in normal development'. The extended study which is the main focus of the present book was undertaken in order to check the validity of the additional hypothesis of four subphases of the normal separation-individuation process.

The psychological birth of the infant occurs during the separation-individuation phase which Mahler places in the period from the fourth or fifth month to the thirtieth or thirty-sixth month. The concept of separation designates the child's emergence from a symbiotic fusion with the mother. Individuation comprises those developmental achievements which mark the child's assumption of his own individual characteristics.

Mahler counsels attention to the effects of imbalances in development. For example, precocious locomotor development may enable a child to separate physically from the mother and may lead to a premature awareness of separateness before the internal regulatory mechanisms necessary to cope with this awareness are developed. Or an overprotective, infantilizing mother may retard the development of the child's self-awareness despite normal cognitive, perceptual, and affective functions. The concept of the separation-individuation process applies only to the intrapsychic achievement of a sense of separateness in early childhood and not to every new separation or revised feeling of self at any age.

In relation to psychoanalytic theory Mahler sees her work as bearing especially on adaptation and object relationships. The outcome of the separation-individuation phase for the personality and mental health of the child hinges on the quality of the mutual adaptation of mother and child. In the sphere of