ABSTRACT
Although the overall philosophies of Plato (1942), Aristotle (1934), and Freud (1952) were different in many ways, they had at least one view in common: the human soul—or psyche—or mind—was viewed hierarchically; the bottom levels of this hierarchy corresponded to "lower" or vegetative or animal functions, whereas the highest level corresponded to the uniquely human reasoning capacity—or conscious part of the ego. For Plato, the levels were animal, spirited, and rational. For Aristotle, the levels were vegetative, animal, and rational. And for Freud they were the id (wholly unconscious), the unconscious parts of the superego and ego, and the conscious part of the superego and ego.
