frustration–aggression hypothesis
the theory, proposed in 1939 by John Dollard and colleagues, that (a) frustration always produces an aggressive urge and (b) aggression is always the result of prior frustrations. Neal E. Miller, one of the proponents of this theory, later noted that frustration can lead to several kinds of actions but maintained that the urge to aggression will become more dominant as the thwarting continues. In 1989, U.S. psychologist Leonard Berkowitz (1926– ) proposed that the frustration must be decidedly unpleasant to evoke an aggressive urge. Also called aggression–frustration hypothesis.