Skinner bests Piaget and Freud:

Study ranks the top 20th century psychologists: “The rankings were based on the frequency of three variables: journal citation, introductory psychology textbook citation and survey response. Surveys were sent to 1,725 members of the American Psychological Society, asking them to list the top psychologists of the century.

Researchers also took into account whether the psychologists had a National Academy of Sciences membership, were elected as APA president or received the APA Distinguished Scientific Contributions Award, and whether their surname was used as an eponym.” American Psychological Association Monitor