In classical criminology, crime was perceived as a threat to the natural order, and punishing crime involved asserting sovereign authority over those criminals. Enlightenment assumptions implied that the level of punishment inflicted by officials of state should be reduced to a level minimally necessary to keep the cost of criminality higher than the selfish gain the offender would derive from unpunished crime. This utilitarian antithesis to retributive theories of criminology became the legitimation for punishment in 18th century democracies. The positivist antithesis to the science of punishmeent blamed the bulk of the crime problem on biological and moral developmental defects among the poor and set out to make institutional arrangements for the treatment of them. A synthesis was created by 1850 in which a primary task of criminology was to classify offenders according to which theory of sanction fitted the circumstances of each. In the latter 19th century, the view emerged that the poor were pressed to commit crime by their stressful working conditions, which should be improved. Marxists went on to call for revolutionary change rather than evolutionary change. The next perspective assumed the dynamics of a social structure to be the source of crime and its control; proposals for change emerge from a social systems perspective. These modulations in criminology show that the radicals of a new age are bound to find empirical issues unaddressed and unaccounted for by the radical knowledge of old, and that radicalism is vital to the growth of criminology. Thirty-nine references are provided. For related documents, see NCJ 70048-61.