Social Conventions

A social convention is a stable, self-enforcing regularity in behavior that persists because each participant prefers to conform given that others conform. Unlike explicit contracts or legal rules, conventions need no centralized enforcement; their stability derives from the structure of coordination problems themselves.

The concept was formalized by philosopher David Lewis in his 1969 work Convention: A Philosophical Study. Lewis argued that a convention is a behavioral regularity R in a population P, solving a recurrent coordination problem, such that it is common knowledge in P that (a) almost everyone conforms to R, (b) almost everyone expects almost everyone else to conform, and (c) almost everyone prefers to conform given that others do.

Social conventions range from trivial (driving on the right side of the road) to foundational (language, property norms, monetary systems). The stability of a convention does not imply its optimality. Multiple conventions can solve the same coordination problem, and the one that obtains is often historically contingent rather than functionally superior.