How Do You Know?

Why do people form the beliefs and knowledge they hold, and how does that shape their conduct? Russell Hardin argues that this question has to be answered before we can make sense of behavior that looks irrational from the outside. What seems like a mistake to an observer may be sensible once you recognize that two people possess very different information.

Hardin starts from the assumption that people rarely act knowingly against their own interests or purposes. On that view, asking how someone came to hold a belief is a fair way to judge whether their conduct was rational. He builds an essentially economic account of what an individual can realistically come to know, and he applies it to a wide range of everyday matters. These include political participation, religious belief, what the public knows about science, liberalism, culture, extremism, moral convictions, and knowledge held within institutions.

The central claim is that people try to act reasonably while working under tight limits on acquiring knowledge, and that those limits are often severe when the demands placed on them exceed what they can learn. Read this way, many puzzling choices become more intelligible.