Polarities of Experience: Relatedness and Self-Definition in Personality Development, Psychopathology, and the Therapeutic Process. By Sidney J. Blatt. Washington, DC:  American Psychological Association, 2008,  404 pp., $69.95.

Sidney Blatt is a true psychoanalytic pioneer. He has combined astute clinical observation with a clear and long line of research. It is rare to see

both in one individual. His unique combination of the two has yielded a fruitful new theory of both personality and various types of psychological disorders.

Blatt hypothesizes, and has data to support his hypotheses, that individuals tend to evince two central trends—an anaclitic relationship trend and an introjective, self-defining one. Blatt then looks at both a variety of clinical conditions and various types of response to treatment approaches in light of these two central tendencies.

Consider the example of a patient evincing symptoms of depression. If the patient tends toward the anaclitic personality type, the nature of his depression and the issues he is struggling with are likely to be quite different from those seen in the introjective type. The anaclitic patient may have just suffered a loss of relationship and may be yearning for someone to fill the void. In therapy, such an individual may be seeking the warmth and relatedness of the therapist as his primary goal. By contrast, the patient suffering from depression who tends more toward the introjective type may be highly self-critical and self-punishing and have goals in therapy very different from the goals of the anaclitic type. He may, for example, seek insight into his condition, but interpret comments from the therapist in a self-critical way.

Blatt's hypotheses and research are supported by observations of infants and young children in their development of intrapsychic structures. Affect or emotion is central to the infant's development of social and emotional capacities, as well as of intelligence. Initially, in the early months of life, affects such as pleasure lead the infant to, for example, look toward and listen to the mother's voice. This will lead the infant to begin using motor skills—in this instance, turning to find the source of the pleasur