Can theories of evolution explain the development of our capacity for moral judgment and the content of morality itself? If bad behavior punished by the criminal law is attributable to physical causes, rather than being intentional or voluntary as traditionally assumed, what are the implications for rethinking the criminal justice system? Is evolutionary theory and “nature talk,” at least as practiced to date, inherently conservative and resistant to progressive and feminist proposals for social changes to counter subordination and secure equality? This book addresses many of the philosophical, legal, and political issues raised by such questions. It examines the possibilities of a naturalistic ethics, the implications of behavioral morality for reform of the criminal law, the prospects for a biopolitical science, and the relationship between nature, culture, and social engineering.