Classical crime theory is represented by the theoretical study of Jeremy Bentham and Cesare Beccaria. Jeremy Bentham  was a founder of  English utilitarianism. Bentham thought that human beings are hedonistic and act only in their own self-interest. Utilitarianism also considered rational courses of action when people pursue own interests. Utilitarian teachings are an important part of  criminal-justice  ethics today. Neoclassical crime theory is a continuation of classical crime theory tradition. Development of neoclassical crime theory will continue in 1980 with a forming of new sociological theories, i.e. differential association and identification. Although sources that mention neoclassical school and crime theory of criminology are merely sparce, it main contribution to the field of criminology is reflected through the understanding of individual differences of the perpetrators. While classical school was wholly concern with an explanation of crime, neoclassical crime theory saw some flaws in Beccaria's theory of crime. Classical crime theory completely concentrated on the criminal act and positivist crime theory concentrated on the perpetrator. Positivist were obsessed with behavioral prediction and classicist with a crime explanation. Neoclassical crime theory sought to improve the stances towards perpetrators who should have an impact on the level of guilt and severity of punishment. Not all perpetrators should be treated in the same fashion, because the evident differences exist among them. Crime is a result of many conditions that have ultimately influenced on the perpetrators to commit it. Representative of neoclassical criminology theory, Gabriel Tarde published the book "Penal philosophy" in 1890. Gabriel Tarde was a French sociologist and founder of neoclassical criminology school. In his book Tarde criticizes classical and positivist criminology and takes the best from both criminology. Neoclassical criminology theory considers  age, gender and social class of the perpetrators. The perpetrators are people who think, feel, act and criminal behavior is learned within groups by imitation and identification.