Triangulation is a manipulation tactic where one person will not communicate directly with another person, instead using a third person to relay communication to the second, thus forming a triangle. It is also a form of splitting in which one person manipulates a relationship between two parties by controlling communication between them.
In the field of psychology, triangulations are necessary steps in the child's development when a two-party relationship is opened up by a third party into a new form of relationship. So the child gains new mental abilities. The concept was introduced in 1971, by the Swiss psychiatrist Dr. Ernest 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. In this presentation, the mother is the early caregiver with a nearly "symbiotic" relationship to the child, and the father lures the child away to the outside world, resulting in the father being the third party. Abelin later developed an organizer- and triangulation-model, in which he based the whole human mental and psychic development on several steps of triangulation.
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. In a 1978 paper, the child psychoanalyst Dr. 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 reengulfment by the mother which leads to an early identification with the father, preceding that of the classical Oedipus complex. This was also related to the work in Separation-Individuation theory of child development by the psychoanalyst Margaret Mahler.
In the context of narcissism, triangulation is when the narcissist attempts to control the flow, interpretation, and nuances of communication between two separate actors or groups of actors. Ensuring communications flow through, and constantly relate back to the narcissist provides a feeling of importance. Common scenarios include a parent attempting to control communication between two children, or an emotionally abusive partner attempting to control communication between the other partner and the other partner's friends and family. A narcissistic person wants to ensure the other actors communicate through them but remain otherwise isolated. In some cases narcissists will use control of communication to drive a wedge between the other parties. This can be done by falsely making one of the actors or groups of actors into a scapegoat for problems that the narcissist is actually responsible for or that are otherwise unrelated. In addition the narcissist may falsely credit the other actor with saying or thinking something hurtful, or may put too much emphasis on an aspect of something that was said to them that ignores the wider context.
Alternatively, the narcissist may attempt to use triangulation to put a third actor between them and someone they are commonly in conflict with. Rather than communicating directly with the actor they're in conflict with, the narcissist flows communication supporting his or her case through a third actor in an attempt to make the communication more credible.
In family therapy, the term triangulation is most closely associated with the work of Murray Bowen. Bowen theorized that a two-person emotional system is unstable in that it forms itself into a three-person system or triangle under stress.
In the family triangulation system the third person can either be used as a substitute for the direct communication, or can be used as a messenger to carry the communication to the main party. Usually this communication is an expressed dissatisfaction with the main party. For example, in a dysfunctional family in which there is alcoholism present, the non-drinking parent will go to a child and express dissatisfaction with the drinking parent. This includes the child in the discussion of how to solve the problem of the alcoholic parent. Sometimes the child can engage in the relationship with the parent, filling the role of the third party, and thereby being "triangulated" into the relationship. Or, the child may then go to the alcoholic parent, relaying what they were told. In instances when this occurs, the child may be forced into a role of a "surrogate spouse" The reason that this occurs is that both parties are dysfunctional. Rather than communicating directly with each other, they utilize a third party. Sometimes, this is because it is unsafe to go directly to the person and discuss the concerns, particularly if they are alcoholic and/or abusive.
The Perverse Triangle was first described in 1977 by Jay Haley 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 perverse triangle concept has been widely discussed in professional literature. Bowen called it the pathological triangle, while Minuchin called it the rigid triangle.
A dramatized example of Triangulation and Splitting can be viewed in the TV show Law & Order Criminal Intent, Season 4, Episode 1 entitled "Semi-Detached" in which Detective Bobby Goren (Vincent D'Onofrio) refers to a psychological strategy of "splitting" used by the antagonist to drive a wedge between Goren and his partner, Detective Eames (Kathryn Erbe). It is an example of classic manipulative triangulation or divide and conquer through hidden and subtle means by the third party and under the pretense of caring about those who are being turned against each other.