This was not merely an idea, but a revelation. At the sight of that skull, I seemed to see all of a sudden, lighted up as a vast plain under a flaming sky, the problem of the nature of the criminal--an atavistic being who reproduces in his person the ferocious instincts of primitive humanity and the inferior animals. Thus were explained anatomically the enormous jaws, high cheek-bones, prominent superciliary arches, solitary lines in the palms, extreme size of the orbits, handle-shaped or sessile ears found in criminals, savages, and apes, insensibility to pain, extremely acute sight, tattooing, excessive idleness, love of orgies, and the irresistible craving for evil for its own sake, the desire not only to extinguish life in the victim, but to mutilate the corpse, tear its flesh, and drink its blood. I was further encouraged in this bold hypothesis by the results of my studies on Verzeni, a criminal convicted of sadism and rape, who showed the cannibalistic instincts of primitive anthropophagists and the ferocity of beasts of prey. The various parts of the extremely complex problem of criminality were, however, not all solved hereby. The final key was given by another case, that of Misdea, a young soldier of about twenty-one, unintelligent but not vicious. Although subject to epileptic fits, he had served for some years in the army when suddenly, for some trivial cause, he attacked and killed eight of his superior officers and comrades. His horrible work accomplished, he fell into a deep slumber, which lasted twelve hours and on awaking appeared to have no recollection of what had happened. Misdea, while representing the most ferocious type of animal, manifested, in addition, all the phenomena of epilepsy, which appeared to be hereditary in all the members of his family. It flashed across my mind that many criminal characteristics not attributable to atavism, such as facial asymmetry, cerebral sclerosis, impulsiveness, instantaneousness, the periodicity of criminal acts, the desire of evil for evil's sake, were morbid characteristics common to epilepsy, mingled with others due to atavism. Thus were traced the first clinical outlines of my work which had hitherto been entirely anthropological. The clinical outlines confirmed the anthropological contours, and _vice versâ_; for the greatest criminals showed themselves to be epileptics, and, on the other hand, epileptics manifested the same anomalies as criminals. Finally, it was shown that epilepsy frequently reproduced atavistic characteristics, including even those common to lower animals.