Splitting is a normal mechanism of the first stages of the ego, arising initially from inability to integrate the first introjections of early object relationships, and then used to keep the introjections that are good individually from conflict with one another. Later the identification systems synthesize into higher organizations such as the self and representational world and neutralize aggression. Excessive splitting interferes with the differentiation of primary and secondary autonomy, and weakens the capacity for repression and higher defensive operations. Clinical observations are supplied as the basis for these conclusions.