Negativity Bias
The human tendency to react more strongly to negative stimuli than to positive stimuli of equal magnitude. A single insult outweighs five compliments; a single threat dominates attention more than five reassurances. The bias is evolutionarily adaptive — missing a predator was fatal, missing a piece of good news was not — but it is also the primary lever propagandists pull. Fear, outrage, and disgust spread further and faster than calm or joy precisely because negativity-biased brains amplify them.