Mark C. Murphy

The moral formulation of philosophical anarchism is that most persons, even in just political communities, do not have a moral obligation to obey the law. The epistemological formulation of philosophical anarchism is that most persons are unjustified in believing that they have a moral obligation to obey the law. But the philosophical anarchists’ argument strategies do not, and in fact cannot, show that belief in the moral obligation to obey the law is unjustified. And, further, given that most persons in just political communities do believe that they are under such an obligation, the moral requirement that one ought to act in accordance with one’s conscience implies that most persons have a moral obligation to obey the law. Thus the moral formulation of philosophical anarchism is false and the epistemological formulation unjustified.

Natural law theory has been undergoing a revival, especially in political philosophy and jurisprudence. Yet, most fundamentally, natural law theory is not a political theory, but a moral theory, or more accurately a theory of practical rationality. According to the natural law account of practical rationality, the basic reasons for actions are basic goods that are grounded in the nature of human beings. Practical rationality aims to identify and characterize reasons for action and to explain how choice between actions worth performing can be appropriately governed by rational standards. These standards are justified by reference to features of the human goods that are the fundamental reasons for action. This book is a defence of a contemporary natural law theory of practical rationality, demonstrating its inherent plausibility and engaging systematically with rival egoist, consequentialist, Kantian and virtue accounts.