Understanding the causes of behavior is one of philosophy's oldest challenges. In analyzing human desires, Bertrand Russell's position was clearly related to that of psychological hedonism. Still, though he seems to have held quite consistently that desires and emotions govern human behavior, he claimed that they do not necessarily do so by making us want to maximize pleasure. This claim is related to several being made in today's psychology and philosophy. I point out a string of facts and arguments indicating (...) the weakness of this position, and briefly discuss the possibility of developing a set of assumptions regarding behavioral causation common to students of thinking and behavior. (shrink)