The Concept of Anxiety
All of Kierkegaard's books have either a preface, dedication, or prayer at the beginning. This book includes a lengthy introduction. "The Concept of Anxiety" was published on exactly the same date as "Prefaces", June 17, 1844. Both books deal with Hegel’s idea of mediation. Mediation is a common thread throughout Kierkegaard’s works. His work up to this point was to show that faith was being mediated by knowledge. Here he takes up the questions of sin and guilt.
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).