A criminal is a man who violates the laws decreed by the State to regulate the relations between its citizens, but the voluminous codes which in past times set forth these laws treat only of crime, never of the criminal. That ignoble multitude whom Dante relegated to the Infernal Regions were consigned by magistrates and judges to the care of gaolers and executioners, who alone deigned to deal with them. The judge, immovable in his doctrine, unshaken by doubts, solemn in all his inviolability and convinced of his wisdom, which no one dared to question, passed sentence without remission according to his whim, and both judge and culprit were equally ignorant of the ultimate effect of the penalties inflicted.

In 1764, the great Italian jurist and economist, Cesare Beccaria first called public attention to those wretched beings, whose confessions (if statements extorted by torture can thus be called) formed the sole foundation for the trial, the sole guide in the application of the punishment, which was bestowed blindly, without formality, without hearing the defence, exactly as though sentence were being passed on abstract symbols, not on human souls and bodies.

The Classical School of Penal Jurisprudence, of which Beccaria was the founder and Francesco Carrara the greatest and most glorious disciple, aimed only at establishing sound judgments and fixed laws to guide capricious and often undiscerning judges in the application of penalties. In writing his great work, the founder of this School was inspired by the highest of all human sentiments—pity; but although the criminal incidentally receives notice, the writings of this School treat only of the application of the law, not of offenders themselves.

This is the difference between the Classical and the Modern School of Penal Jurisprudence. The Classical School based its doctrines on the assumption that all criminals, except in a few extreme cases, are endowed with intelligence and feelings like normal individuals, and that they commit misdeeds consciously, being prompted thereto by their unrestrained desire for evil. The offence alone was considered, and on it the whole existing penal system has been founded, the severity of the sentence meted out to the offender being regulated by the gravity of his misdeed.

The Modern, or Positive, School of Penal Jurisprudence, on the contrary, maintains that the anti-social tendencies of criminals are the result of their physical and psychic organisation, which differs essentially from that of normal individuals; and it aims at studying the morphology and various functional phenomena of the criminal with the object of curing, instead of punishing him. The Modern School is therefore founded on a new science, Criminal Anthropology, which may be defined as the Natural History of the Criminal, because it embraces his organic and psychic constitution and social life, just as anthropology does in the case of normal human beings and the different races.

If we examine a number of criminals, we shall find that they exhibit numerous anomalies in the face, skeleton, and various psychic and sensitive functions, so that they strongly resemble primitive races. It was these anomalies that first drew my father's attention to the close relationship between the criminal and the savage and made him suspect that criminal tendencies are of atavistic origin.

When a young doctor at the Asylum in Pavia, he was requested to make a post-mortem examination on a criminal named Vilella, an Italian Jack the Ripper, who by atrocious crimes had spread terror in the Province of Lombardy. Scarcely had he laid open the skull, when he perceived at the base, on the spot where the internal occipital crest or ridge is found in normal individuals, a small hollow, which he called median occipital fossa (see [Fig. 1]). This abnormal character was correlated to a still greater anomaly in the cerebellum, the hypertrophy of the vermis, i.e., the spinal cord which separates the cerebellar lobes lying underneath the cerebral hemispheres. This vermis was so enlarged in the case of Vilella, that it almost formed a small, intermediate cerebellum like that found in the lower types of apes, rodents, and birds. This anomaly is very rare among inferior races, with the exception of the South American Indian tribe of the Aymaras of Bolivia and Peru, in whom it is not infrequently found (40%). It is seldom met with in the insane or other degenerates, but later investigations have shown it to be prevalent in criminals.

This discovery was like a flash of light. "At the sight of that skull," says my father, "I seemed to see all at once, standing out clearly illumined as in a vast plain under a flaming sky, the problem of the nature of the criminal, who reproduces in civilised times characteristics, not only of primitive savages, but of still lower types as far back as the carnivora."