Yet unlike some historians, who distrust any application of psychological theory to historical figures, Dr. Redlich believes one cannot adequately assess Hitler's actions without taking into account not only the historical facts, but the Nazi leader's ''psychological reality.'' For example, Hitler believed that his father was half-Jewish and had died of syphilis. These beliefs, the author argues, may have affected the Nazi leader's behavior, whether or not they were true. (There is no clear evidence, Dr. Redlich writes, to support either claim.)
Dr. Redlich theorizes that Hitler may have thought his physical abnormalities -- his hypospadia and spina bifida occulta -- were signs that he had inherited syphilis from his father. And his rage at this may have fueled his anti-Semitism, and his obsession with syphilis as a ''Jewish disease,'' a theme he dwelled upon for 10 pages in ''Mein Kampf.''
Indicators of Hitler's peculiarities in later adulthood, of course, are abundant, from his sexual inhibition (he may never have had sexual intercourse with Eva Braun, Dr. Redlich writes) to his phobias of disease, his explosive rages, his delusions and his conviction that he would die at an early age (he died at 56). In his book, Dr. Redlich runs through a list of psychiatric symptoms -- paranoia, narcissism, anxiety, depression, hypochondria, to name a few -- and finds some evidence for every one. Proof that Hitler was overtly self-destructive or sexually perverse is sparser and less compelling, the author says.
Yet Dr. Redlich concludes that attaching a formal psychiatric diagnosis to the Nazi leader is not very useful. When applying such diagnoses, he writes, he often feels ''as if I were in a cheap clothing store: Nothing fits, and everything fits.'' Ultimately, the psychiatrist portrays Hitler as a man who was more than the sum of his pathology, entirely responsible for his actions.