Rational Ignorance vs. Rational Irrationality

Instructor: Gaines Arnold
Do people who vote do so in a rational way? This lesson looks at the rational irrationality of Bryan Caplan and compares it to rational ignorance. The lesson defines terms, provides examples of each and then looks at Caplan's argument for rational irrationality.

The Problem with Voting

When Marvin stood at the voting box, he remembered conversations with friends about some of the issues presented. He had listened to different opinions but had never taken the time to research them for himself. He decided he was too busy to look at the bills fully, so he decided to vote based on the scant understanding he had of most of the issues.

Then he came to a bill that seemed to go against a core belief of his. He didn't need anyone else's opinion this time. He knew that his view was correct and voted based on previously held beliefs. Unfortunately, he didn't know that his beliefs had been rationally challenged and found to be false. Marvin stood in the ballot box and made his decisions based on both rational ignorance and rational irrationality.

Definition of Terms

It may seem that both terms present an oxymoron (speech in which seemingly contradictory terms are used in combination), however, they aptly describe two modes of thought. Rationality can be defined as something that is based on a logical thought process. So when someone thinks rationally, they are using a thought process that the individual deems reasonable. It doesn't matter whether the process seems rational to someone else or not. To understand the two following terms, this is an important distinction.

Rational Ignorance

Ignorance is the lack of information. Thus, it is not the inability to understand information, but the lack of it. Sometimes this is willful (as in the individual does not want to be less ignorant) or it can be simply that the knowledge has not yet been acquired. From this, it is possible to understand the definition of rational ignorance which is deciding that acquiring a certain unit of knowledge is not worth the cost. This means that the individual decides that their time would be better spent on some activity other than acquiring said piece of knowledge.

Rational Irrationality

Again, it is necessary to examine irrationality first. Irrationality is when an individual does not reason when they make a decision. Thus, it is the opposite of rationality. However, when the two terms are used in conjunction, rational irrationality, the term refers to someone who makes a seemingly reasoned assessment based on unreasonable evidence. When a person believes in something and thinks the belief is rational despite a preponderance of evidence to the contrary, you arrive at that the concept of rational irrationality.

Examples of the Two Terms

Bryan Caplan

Research, specifically that done by economist Bryan Caplan, looked at action and belief systems to provide examples of rational ignorance and rational irrationality. People choose a religion based on family, cost, or some other measure, then they adhere to those beliefs. When asked whether they believe in certain aspects of their religion (for example creation versus evolution) people will often side with their religion.

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