A view of the background of Freudian theory.

A major concern of nineteenth century scientists was to delineate the objective units or entities with which science deals. While some philosophers of science abandoned the search as futile and tried to redefine science, investigators in the biological sciences and the sciences of man attempted to discover new entities upon which to base their disciplines. A new understanding of hypnotism gave Freud the opportunity to isolate objective entities within the mind and to found a psychology on that basis.