Anxiety
The philosopher Søren Kierkegaard, in "The Concept of Anxiety" (1844), described anxiety or dread associated with the "dizziness of freedom" and suggested the possibility for positive resolution of anxiety through the self-conscious exercise of responsibility and choosing. In "Art and Artist" (1932), the psychologist Otto Rank wrote that the psychological trauma of birth was the pre-eminent human symbol of existential anxiety and encompasses the creative person's simultaneous fear of – and desire for – separation, individuation, and differentiation.
Parataxical Integration
The concept first appeared in Sullivan's "The Interpersonal Theory of Psychiatry", published in 1953. It was developed further by his protégé, Lorna Smith Benjamin, in her "Interpersonal Diagnosis and Treatment of Personality Disorders" (1996). Benjamin saw parataxical integration as typical in the interpersonal behavior of couples with unresolved autonomy (i.e. separation, boundary) and identity issues. Erik Erikson had himself described the unconscious, reciprocal reactivation (without using Sullivan’s terms) in his essay, “The Problem of Ego Identity,” and in "Identity and Anxiety", by Stein "et al". (1960).