Dollard Frustration-Aggression Hypothesis
Dollard proposed the frustration-aggression hypothesis, a social-psychological theory that argues that aggression is always the outcome when we are prevented from achieving our goals.
The frustration-aggression hypothesis is based on the psychodynamic concept of catharsis (releasing strong emotions).
If our attempt to achieve a goal is blocked by an external factor, this leads to frustration, which creates an aggressive drive, leading to aggressive behaviour such as verbal outburst or physical violence.
If the source of frustration is abstract, too powerful or unavailable at the time, the aggression is displaced onto a physical, weaker or available alternative.