Some early similarities and later differences between Bertrand Russell and B. F. Skinner.

B. F. Skinner credited Bertrand Russell with converting him to behaviorism and with writing one of the books that most influenced him. Particularly in Skinner's early work, there are similarities between Skinner and Russell that extend across mathematics, determinism, positivism, verbal behavior, future communities, evolution, and pragmatism. Later, Skinner's views changed, and he parted company with Russell in most of these areas. Perhaps the most dramatic and fundamental departure came when Skinner embraced pragmatism, which Russell said he "hated." However, there was a time during which Russell wrote favorably of pragmatism as a view for science. Although the similarities between Skinner and Russell may have resulted from common cultural influences, Russell appears to deserve credit for leading Skinner into the stimulus-response behaviorism of two-term necessities; he may also deserve some credit for helping to lead him out of it and into the selectionist behaviorism of three-term contingencies.