It is generally recognized that modern personality theory dates from the closing decades of the nineteenth century when Sigmund Freud advanced his theories of psychopathology, which were then extended to normals. On first consideration, this seems an odd direction to take—moving from the abnormal to the normal behavioral pattern. But there is something irreducibly human albeit "unnatural" about a disordered mind. Neurotics do not listen to reason, yet they have their reasons. Psychotics believe in the most preposterous things, living out a phantasy realm that is stretched beyond recognition by those of us who populate the everyday, "natural" environment.