Social behaviour is but an expression of instinctive mechanisms whereby the aggressive instinct is of particular importance, having given rise to most of the complexity of social behaviour through processes of phylogenetic and cultural ritualisation. The role of the aggressive instinct is to dynamically maintain the ranking order in a group, and much of social interaction is concerned with this, including monetary exchange.

What is certain, is that with the elimination of aggression, … the tackling of a task or problem, the self-respect [in] everything that a man does from morning till evening, from the morning shave to the sublimest artistic or scientific creation, would lose all impetus; everything associated with ambition, ranking order, and countless other equally indispensable behaviour patterns would probably also disappear from human life.

— Konrad Lorenz (1963/2002, p. 269)