APAvar: Segal, Hanna (1973). Intoduction to the Work of Melanie Klein. Basic Books.
Link: https://worldcat.org/en/title/949553719
page 35:
No experience in human development is ever cast aside or obliterated; we must remember that in the most normal individual there will be some situations which will stir up the earliest anxieties and bring into operation the earliest mechanisms of defence. One of the achievements of the paranoid-schizoid position is splitting. It is splitting which allows the ego to emerge out of chaos and order its experiences. ... It is the basis of what is later to become the faculty of discrimination .... other aspects of splitting which remain and important in mature life. For instance, the ability to pay attention, or to suspend one's emotions in order to form an intellectual judgement, would not be achievable without the capacity for temporary reversible splitting.
page 36:
With splitting are connected persecutory anxiety and idealization. Of course both, if retained in their original form in adulthood, distort judgement, but some elements of persecutory anxiety and idealization are always present and play a role in adult emotions. Some degree of persecutory anxiety is a precondition for being able to recognize, appreciate and react to actual situations of danger in external conditions. Idealization is the basis of the bellief in the goodness of objects and oneself, and is a precursor to good object-relationships. ... Projective identification, too has its valulable aspects. To begin with, it is the earliest form of empathy and it is on projective and well as introjective identification that is based the capacity to "put oneself into another person's shoes." Projective identification also provides the basis of the earliest form of symbol formation. By projecting parts of itself into the object and identifying parts of the object with parts of the self, the ego forms its first most primitive symbols.
page 73:
Reality testing exists from birth. The child "tastes" his experiences, and classifies them as good or bad. But in the depressive position this reality testing becomes more established and meaningful and more closely connected with psychic reality.
page 75:
The pain of mourning experienced in the deprresive position, and the reparative drives developed to restore the loved internal and external objects are the basis of creativity and sublimation. ...
The processes of sublimation and symbol formation are closely linked and are both the outcome of conflicts and anxieties pertaining to the depressive position.
page 76:
In the depressive position ... the whole climate of thought changes. It is at this time that the capacities for linking and abstraction develop, and for the basis of the kind of thinking we look for in the mature ego, in contrast to the disjointed and concrete thinking characteristic of the paranoid-schizoid poosition.
page 80:
The depressive position is never fully worked through. The anxieties pertaining to ambivalence and guilt, as well as situations of loss, which reawaken depressive experiences, are always with us.