In this chapter, we follow up on the work of other scholars who have recently cautioned about the dangers of ideological uniformity in the social sciences. We forward the paranoid egalitarian meliorist (PEM) model to help account for bias in the social sciences. Paranoid is not a pejorative term but describes a sensitivity to perceived threats to egalitarian meliorism. We argue (1) that many social scientists are paranoid egalitarian meliorists; (2) that they are therefore very sensitive to threats to a sacred egalitarian narrative; (3) that this sensitivity may be excessive (at least in the domain of science) and may cause researchers to unfairly reject research that challenges egalitarianism; (4) that this may then lead to the marginalization of individuals who forward controversial theories and/or data; and (5) that these tendencies lead to bias in the social sciences. We conclude with a couple of remedies that may alleviate the worst excesses of PEM in the social sciences.