Building a simple model on the fragility of preferences about how to vote delivers an number of different and realistic implications for the demand for public policies and political candidates, the supply of public policies and political candidates, and, ultimately, the determinants of public policy. The model explains why so many studies have found voters not voting in their (narrowing defined) self-interest, why minorities are not exploited under majoritarian voting, why interest groups have an important influence on public policy, why public decisions are so weakly correlated with voting rules, and why conformity is more common in political than private life.