  In its historical foundations, methodological behaviorism shares with analytical behaviorism the influence of positivism. One of the main goals of positivism was to unify psychology with natural science. Watson wrote that “psychology as a behaviorist views it is a purely objective experimental branch of natural science. Its theoretical goal is … prediction and control” (1913, p. 158). Watson also wrote of the purpose of psychology as follows: “To predict, given the stimulus, what reaction will take place; or, given the reaction, state what the situation or stimulus is that has caused the reaction” (1930, p.  11).