Notes on the Differentiating Function of the Ego

IN 1930 NUNBERG (1931) INTRODUCED into ego psychology the concept of the synthetic function of the ego. In a comprehensive presentation he made clear the role of the synthetic function in a variety of mental operations, among them mediating the demands of the id, the superego, and the outer world; bringing about causal thinking; and producing the symptom as a compromise formation between impulse and defense. Hartmann (1939a) later suggested that, alongside a synthetic function, a differentiating function of the ego must be recognized as playing an equally important role in psychic activity. He alluded to a paper "The Differentiation and Integration of Psychic Processes" that Spitz had presented to the Vienna Psycho-Analytical Society in 1936, which Hartmann considered relevant to the subject. Unfortunately, the paper was never published. The synthetic function of the ego has a secure niche in psychoanalytic theory and is often referred to. By contrast, Hartmann's remark that the differentiating function has been less fully explored seems as true today as it was in 1939. Hence, it seemed worthwhile to find out whether further study might cast more light on the subject: its origins, mode of operation, the consequences of its effective functioning as well as of its failure to function under certain conditions.

Hartmann's terse, synoptic statements about the differentiating function can be very briefly summarized. Differentiation must be recognized, along with synthesis, as an