  Salience plays two distinct roles in Lewis’s account, corresponding to the following two questions: How do conventions arise? and Why do people conform to convention? The former question concerns dynamics (i.e., the factors governing how conventions originate and evolve over time), while the latter concerns statics (specifically, the rational structure that sustains a convention at a given moment). Lewis’s answer to the first question is that agents initially select some equilibrium either by chance, agreement, or intrinsic salience. The equilibrium gradually becomes more salient through precedent, until eventually it becomes a convention. Lewis’s answer to the second question is that a pre-existing convention is so overwhelmingly salient that agents expect one another to abide by it, an expectation which furnishes reason to conform.