Herbert "Harry" Stack Sullivan (February 21, 1892, Norwich, New York – January 14, 1949, Paris, France) was an American Neo-Freudian psychiatrist and psychoanalyst who held that "personality can never be isolated from the complex interpersonal relationships in which [a] person lives" and that "[t]he field of psychiatry is the field of interpersonal relations under any and all circumstances in which [such] relations exist". Having studied therapists Sigmund Freud, Adolf Meyer, and William Alanson White, he devoted years of clinical and research work to helping people with psychotic illness. Early life Sullivan was a child of Irish immigrants and grew up in the then anti-Catholic town of Norwich, New York, resulting in a social isolation which may have inspired his later interest in psychiatry. He attended the Smyrna Union School, then spent two years at Cornell University from 1909, receiving his medical degree in Chicago College of Medicine and Surgery in 1917. Work Along with Clara Thompson, Karen Horney, Erich Fromm, Otto Allen Will, Jr., Erik H. Erikson, and Frieda Fromm-Reichmann, Sullivan laid the groundwork for understanding the individual based on the network of relationships in which they are enmeshed. He developed a theory of psychiatry based on interpersonal relationships where cultural forces are largely responsible for mental illnesses (see also social psychiatry). In his words, one must pay attention to the "interactional", not the "intrapsychic". This search for satisfaction via personal involvement with others led Sullivan to characterize loneliness as the most painful of human experiences. He also extended the Freudian psychoanalysis to the treatment of patients with severe mental disorders, particularly schizophrenia. Besides making the first mention of the significant other in psychological literature, Sullivan developed the idea of the "Self System", a configuration of the personality traits developed in childhood and reinforced by positive affirmation and the security operations developed in childhood to avoid anxiety and threats to self-esteem. Sullivan further defined the Self System as a steering mechanism toward a series of I-You interlocking behaviors; that is, what an individual does is meant to elicit a particular reaction. Sullivan called these behaviors Parataxical Integrations and he noted that such action-reaction combinations can become rigid and dominate an adult's thinking pattern, limiting their actions and reactions toward the world as the adult sees the world and not as it really is. The resulting inaccuracies in judgment Sullivan termed parataxic distortion, when other persons are perceived or evaluated based