The sociology of punishment has developed as part of a more general question: how are order and authority to be maintained in modern society? Sociology, like the steam engine, is very much an invention of the industrial revolution. At the core of the discipline are questions to do with social order, with how the rules of society are transmitted from one generation to the next, and how people are induced to behave - most people, most of the time - socially rather than anti-socially. In particular, sociology has homed in on the question of how modern industrial society, which is characterized by the demise of traditional sources of order and authority such as religion and absolute monarchy, and where parents do not generally have economic power over their adult children, manages to maintain order and, indeed, to maintain any sense of being 'a society'. How, in other words, do societies change, but still continue to exist? Pre-sociological political philosophers, such as Herbert Spencer, thought that people act socially because it is in their own interests to do so; sociological thinkers such as Durkheim and Marx questioned this identity between self-interest and social interest, and analysed the ways in which people are conditioned to take the social inter¬est to be their own interest.