The three main schools in criminology are classical school, positivist school, and Chicago school. The classical school focuses on free will and deterrence, the positivist school emphasizes biological, psychological, and sociological factors in criminal behavior, and the Chicago school examines the social environment's impact on crime.

Ultimately, positivist criminology sought to identify other causes of criminal behavior beyond choice. The basic premises of positivism are measurement, objectivity, and causality. Early positivist theories speculated that there were criminals and non-criminals

Cesare Lombroso is considered the father of the biological approach within the positivist school of criminology. Lombroso believed that criminal behavior was determined by biological factors and that he could identify criminals by physical characteristics.

Positivist calendar was created in 1849.

The positivist school of criminology embraced a scientific approach to understanding crime, focusing on biological, psychological, and social factors that contribute to criminal behavior. They believed that individuals were not solely responsible for their actions and that factors beyond their control could influence criminal behavior. Positivist criminologists advocated for rehabilitation and treatment rather than punishment for criminals.