Backstabbing

Betrayal is the breaking or violation of a presumptive contract, trust, or confidence by that produces moral and psychological conflict within a relationship amongst individuals, between organizations or between individuals and organizations. Often betrayal is the act of supporting a rival group, or it is a complete break from previously decided upon or presumed norms by one party from the others. Someone who betrays others is commonly called a traitor or betrayer. Betrayal is also a commonly used literary element and is often associated with or used as a plot twist.

Discovering the Meaning of Treachery Through Jane Austen, writes that "there hastrayal as the breaking of a social contract; however, critics of this approach claim that the term social contract does not accurately reflect the conditions and motivations for, and effects of, betrayal. Philosophers Judith Shklar and Peter Johnson, authors of The Ambiguities of Betrayal and Frames of Deceit respectively, contend that while no clear definition of betrayal is available, betrayal is more effectively understood through literature.

AI researcher Selmer Bringsjord made betrayal the core of a storytelling program BRUTUS. In Artificial Intelligence and Literary Creativity: Inside the Mind of BRUTUS, a Storytelling Machine, betrayal is defined operationally in computer language as basically as knowingly thwarting another out of something that ought to occur.

Jackson explains why a clear definition is needed:

Ben-Yehuda's 2001 work ("Betrayals and Treason Violations of Trust and Loyalty" Westview Press) framed all forms of betrayals and treason under a unifying analytical framework using loyalty, trust and moral boundaries as explanatory tools.

An act of betrayal creates a constellation of negative behaviours, thoughts, and feelings in both its victims and its perpetrators. The interactions are complex. The victims exhibit anger and confusion, and demand atonement from the perpetrator; who in turn may experience guilt or shame, and exhibit remorse. If, after the perpetrator has exhibited remorse or apologized, the victim continues to express anger, this may in turn cause the perpetrator to become defensive, and angry in turn. Acceptance of betrayal can be exhibited if victims forego the demands of atonement and retribution; but is only demonstrated if the victims do not continue to demand apologies, repeatedly remind the perpetrator or perpetrators of the original act, or ceaselessly review the incident over and over again.

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Wikipedia