Abstract

Self-interest voting is irrational when it has even a small cost, but it can be rational for those who care about others; its expected utility (EU) may exceed its cost. For cosmopolitan voters (those who care about outsiders), the EU of voting increases with the number of affected others. The EU of voting for the good of the world now and in the future can thus be large. In some cases, the EU of parochial voting (e.g., considering only one's nation) may not cross the cost threshold, but cosmopolitan voting can cross it. I apply these principles to various kinds of voting. And I compare voting to charity. Voting has the advantage of enlisting the coercive power of the state, but charity can be more focused on effective policies. I discuss campaign contributions, and I conclude with a discussion of the existence of utilitarian voters.