One of the foundational principles of economics is that people respond to incentives. In his book The Organization of Inquiry, Gordon Tullock applies that lesson to the scientific process. On page 154, he shows why most social scientists are timid creatures who would rather affirm popular prejudices than make bold new discoveries:
We have already discussed the tendency of researchers in the social sciences to avoid dangerous issues, to confine their investigations to “safe” subjects and “safe” conclusions. The bulk of the money available for “inducing” such research comes either from essentially charitable endowments or from government organizations (universities, of course, partake of both) and is likely to become unavailable to a man who annoys people with his discoveries. As a result, the students in this field have a strong tendency to devote large amounts of effort to “confirming” popular opinions.