Downs's logic
Downs (1957) treated voters as rational actors weighing costs and benefits. Comparing candidates' policies carefully requires time and effort spent reading newspapers and searching for information, yet in an election with millions of voters the chance that one vote changes the outcome is close to zero. The expected personal benefit of a better-informed choice is therefore very small, so it is rational not to acquire the information. The same logic applies to voting itself and leads to the paradox of voting: why do people vote at all? It is a classic application of rational choice theory to politics.
Information shortcuts
Others object that voters do not vote at random. Popkin (1991) argued that voters use cues such as parties, endorsing groups and candidates' images as information shortcuts, reaching reasonably sensible judgments with little information, which he called low-information rationality. Lupia (1994) reported that in California insurance reform referendums, voters who knew only which side the insurance industry supported voted much like voters who knew the policies in detail. Shortcuts, however, do not always work well.
Information effects and democracy
Analyzing US presidential election data, Bartels (1996) reported information effects: lack of information shifts votes systematically, enough that outcomes might differ if all voters were fully informed. Somin (1998) argued that voter ignorance poses a serious problem for the democratic ideal of citizens controlling government. Caplan (2007) went further, proposing rational irrationality: because correcting mistaken beliefs also costs individuals almost nothing in benefit, people keep emotionally comfortable but mistaken economic beliefs. These ideas are also used to explain the collective action dilemma and rent-seeking.
FAQ
- What is rational ignorance in simple terms?
- If the effort of finding something out is greater than the benefit of knowing it, staying uninformed is actually rational. Studying policy less because one vote is unlikely to change an election is the classic example.
- How does rational ignorance differ from rational irrationality?
- Rational ignorance means not acquiring information at all, while rational irrationality means keeping emotionally comfortable but mistaken beliefs even when information is available, because correcting them costs the individual almost nothing in benefit.
Sources reviewed: 2026-10-26
References
- Downs, A. (1957). An Economic Theory of Democracy. New York: Harper & Row. The original source of the rational ignorance argument.
- Downs, A. (1957). An economic theory of political action in a democracy. Journal of Political Economy, 65(2), 135–150. A concise article version of Downs's theory.
- Popkin, S. L. (1991). The Reasoning Voter: Communication and Persuasion in Presidential Campaigns. Chicago: University of Chicago Press. Low-information rationality and voter shortcuts.
- Lupia, A. (1994). Shortcuts versus encyclopedias: Information and voting behavior in California insurance reform elections. American Political Science Review, 88(1), 63–76. Cues can let uninformed voters mimic informed ones.
- Bartels, L. M. (1996). Uninformed votes: Information effects in presidential elections. American Journal of Political Science, 40(1), 194–230. Information effects systematically shift presidential votes.
- Somin, I. (1998). Voter ignorance and the democratic ideal. Critical Review, 12(4), 413–458. Voter ignorance as a challenge to democratic theory.
- Caplan, B. (2007). The Myth of the Rational Voter: Why Democracies Choose Bad Policies. Princeton, NJ: Princeton University Press. Rational irrationality and systematic voter biases.