Theory, be it psychological, theological, or historical, is constructed by individuals. As Mahoney has chronicled in his massive work, Human Change Processes (1991), humans are not only passive recipients of sensory data from the environment; they are active agents in constructing the data perceived. This shift, called constructionism, is evident not only in
psychology, but in numerous other disciplines and, as Mahoney documents, has been in circulation, in some form or another, since antiquity. Only recently has it gained popularity and more general acceptance from the "mainstream" scientific community.