Social science is under the influence of tradition in sciences, of the cultural and political setting of the environment, and of the social scientist’s own peculiar personal makeup. The result is systematic biases in social science work if we (“the social scientists”) do not protect ourselves by means of sociological and psychological insight into the conditions under which we live and work and by means of the logical methods for purging biases. Myrdal writes this chapter to illustrate his thesis that scientific work is otherwise bound to become biased.