He was a student of Cesare Lombroso, often regarded as the father of criminology.
He rejected the doctrine of free will (which was the main tenet of the Classical School) and supported the position that crime can be understood only if it is studied by scientific methods.
He attempted to formulate a sociological definition of crime that would designate those acts which can be repressed by punishment.
These constituted "Natural Crime" and were considered offenses violating the two basic altruistic sentiments common to all people, namely, probity and piety.
This was more of a psychological orientation than Lombroso's physical-type anthropology.