Norm Cascade

A norm cascade is the rapid, self-reinforcing transition from one informal institution to another, triggered when a critical mass of adopters makes the new norm more attractive than the old. The concept describes how norms that begin with small groups of deviants or entrepreneurs can suddenly sweep through populations once the perceived cost of defection drops below the perceived benefit of conformity. The cascade is not merely a matter of individual preference change; it is a network phenomenon in which each adoption lowers the social cost of the next, creating a feedback loop that can shift collective behavior faster than any formal policy could achieve.

Norm cascades are structurally similar to information cascades in markets and to network effects in technology adoption. But they differ in a crucial respect: norm cascades change the evaluative landscape, not merely the informational one. Once a norm cascade has occurred, the new norm is not just widely practiced; it is widely expected, and deviation is subject to social sanction rather than mere puzzlement. The cascade is therefore a phase transition in the social order — a shift from one attractor basin to another. The role of norm entrepreneurs is to push the system past the tipping point where the cascade becomes self-sustaining.