Dissatisfaction with the classical approach to explain crime first appeared toward the end of the nineteenth century. At that time, crime was viewed by many as a growing problem, and it was observed by many that the harsh punishments of the time seemed to have little effect on criminal offending.
At about the same time, the emerging use of the scientific method, along with the development of social science, began to change how people viewed social problems and how problems might be solved. Charles Darwin described his theory of evolution through natural selection in his book The Origin of Species. Emile Durkheim noted differences in rates of suicide in different regions of France. Durkheim employed observations to develop a social theory of suicide in his book Suicide. Both Darwin and Durkheim were pioneers in the scientific method, which was based on observation. Rather than just thinking about problems, both believed that scientific questions were best answered when scientists first gathered facts and data.
This scientific approach gave rise to the positivist school of criminology. The positivist school saw human behavior as based on a combination of internal and external influences, such as biology, psychology, and social factors. While the classical school still saw crime as emanating from free will and choice, positivism believed it was a combination of internal and external forces that shaped behavior.