If voters accord evidentiary value to one another's reports, revising their own views in the light of them as Bayesian rationality requires, then even relatively small electoral majorities ought to prove rationally compelling and opposition ought rationally to vanish. For democratic theory, that is a jarring result. While there are no resources for avoiding that result within the Bayesian model itself, there are various aspects of the political process lying outside that model which do serve to underwrite the rationality of (...) persistent opposition to majority opinion. Key Words: Bayesian rationality • consensus • political opposition. (shrink)