Revenge is often like biting a dog because the dog bit you.

O’Malley likens revenge to an absurd, self-degrading imitation of the original injury: if a dog bites you, biting it back neither repairs the harm nor restores dignity—it merely makes you behave like the aggressor. The image suggests that retaliation is often irrational, disproportionate, and ultimately self-harming, because it pulls the injured party into the same brutish logic as the offender. The comparison also implies futility: the dog will not understand the “lesson,” and the biter gains no real justice. The aphorism thus favors restraint and moral superiority over reflexive payback, distinguishing justice (measured, principled response) from revenge (impulsive mimicry).