Triangulation is a term in psychology most closely associated with the work of Murray Bowen known as family therapy.
[5] The Perverse Triangle was first described in 1977 by Jay Haley[6] as a triangle where two people who are on different hierarchical or generational levels form a coalition against a third person (e.g., "a covert alliance between a parent and a child, who band together to undermine the other parent's power and authority".
The concept was introduced in 1971 by the Swiss psychiatrist Ernst L. Abelin, especially as 'early triangulation', to describe the transitions in psychoanalytic object relations theory and parent-child relationship in the age of 18 months.
Some earlier related work, published in a 1951 paper, had been done by the German psychoanalyst Hans Loewald in the area of pre-Oedipal behavior and dynamics.
[20] In a 1978 paper, the child psychoanalyst Selma Kramer wrote that Loewald postulated the role of the father as a positive supporting force for the pre-Oedipal child against the threat of re-engulfment by the mother which leads to an early identification with the father, preceding that of the classical Oedipus complex.
[21] This was also related to the work in Separation-Individuation theory of child development by the psychoanalyst Margaret Mahler.
[25] Furthermore, research shows that triangulation can adversely impact children, who may experience increased anxiety and self-blame due to involvement in marital disputes between their parents.