Revenge is often taken against people who were not perpetrators of the original offense, provided that they belong to the perpetrator’s group. People react as if they believed that if one member of a group attacked, then they all did or would. Groups are culturally defined, though the tendency to relate to them is universal. It is proposed that “the enemy” is an inherited category while the identity of the groups placed into that category is learned. Enemies are subject to hate, fear, and coldness (the inhibition of empathy). We are prepared to experience an entire outgroup as “enemy” if any of them attack us. We anticipate the same reaction in outgroups by experiencing them as “enemy” when any of us attack them. We mirror fellow ingroup members’ hatreds.