This contribution discusses the basic thesis that the analysis of the past of psychology is essential for the future of the discipline because it fosters efforts to go beyond the cul-de-sac in which contemporary psychology is entrapped. To this end, two fundamental issues—the unit of knowledge and the fundamental aim of the discipline—are considered. Both these issues represent blind spots in contemporary psychology and, as such, act as constraints on psychology's ability to innovate. On the other hand, these two issues are not new at all but have already been raised and addressed in the past of psychological science. Such earlier efforts can teach a lot to those who are unsatisfied with the morass in which psychology is nowadays bogged down.