The I3 Model: a metatheoretical framework for understanding aggression

- Aggression results from three processes: instigation, impellance, and inhibition.
- Instigation and impellance increase the likelihood and intensity of aggression.
- Inhibition decreases the likelihood and intensity of aggression.
- The three processes interact, generating a 'perfect storm' to produce aggression.

The I3 Model is a general-purpose metatheory. It posits that three orthogonal processes influence the likelihood and intensity of a given behavior, including aggressive behavior. Instigation encompasses immediate environmental stimuli (e.g., provocation) that normatively afford an aggressive response. Impellance encompasses situational or dispositional qualities (e.g., trait aggressiveness) that influence how strongly the instigator produces a proclivity to enact that response. Inhibition encompasses situational or dispositional qualities (e.g., alcohol intoxication) that influence how strongly the proclivity is overridden rather than manifesting in aggressive behavior. Extant evidence supports Perfect Storm Theory-a theoretical perspective derived from the I3 Model-which posits that aggression is especially likely, and especially intense, to the extent that instigation and impellance are strong and inhibition is weak.