Confirmation Bias

This chapter examines confirmation bias, which refers to people’s tendency to attend only to information that agrees with what they already think is true. Confirmation bias is responsible for not only a great deal of denial of scientific evidence but also the actual generation and maintenance of incorrect scientific information. That is, scientific and medical professionals are as prone as anyone else is to “seeing what we believe,” making it especially difficult to help people sort out what is true science from the mistakes and outright fabrications. The chapter demonstrates how confirmation bias, although a highly adaptive human trait, often causes scientific misperceptions due to resistance to the often counterintuitive disconfirmation process of scientific inquiry. It then proposes some ways of countering confirmation bias.