The Ethics of Liberty. It is a tour de force, a remarkable presentation of the moral case for political freedom. What a complement to Man, Economy, and State and Power and Market, Rothbard’s towering contributions to our understanding of free markets!In 1982 Murray Rothbard published his magnum opus in political philosophy,
The first striking feature of Ethics is that the opening five chapters, which comprise part one, seek to establish the validity of natural law, an approach to moral inquiry based on the distinctive nature, faculties, and tendencies of the human being; this approach began with the ancient Greek philosophers and developed through the thought of Catholic and Protestant thinkers, such as St. Thomas Aquinas and Hugo Grotius. (For these religious philosophers, natural law was discoverable through reason, and was separable from theological questions.) One can judge Rothbard’s deep interest in this subject by his first four chapter titles: "Natural Law and Reason," "Natural Law as 'Science,'" "Natural Law versus Positive Law," and "Natural Law and Natural Rights."
Rothbard wanted us to read this material before moving on to such topics as property, enforceable rights, voluntary exchange, aggression, and self-defense. Why?
Because natural law gives meaning to and thus is indispensable to understanding those concepts. It provides the context. He approvingly quoted the natural-law philosopher John Wild: "The philosophy of natural law defends the rational dignity of the human individual." He praised the English natural-law liberals (such as John Locke and the Levellers), "who transformed classical natural law into a theory grounded on methodological and hence political individualism." And he identified the "great failing" of "classical" natural-law thinkers from Plato to Leo Strauss: they were "profoundly statist rather than individualist."
Rothbard’s conviction that individual rights are derived from something more fundamental can be seen in this statement: "The myriad of post-Locke and post-Leveller natural-rights theorists made clear their view that these rights stem from the nature of man and of the world around him."
For Rothbard, individual rights boil down to the right to be free from aggression. (Thus complete freedom in society is possible and realistic.) This is what he wished to derive from the natural law. The principle is not self-evident (though it surely has intuitive appeal). It is no free-floating iceberg. Rather, it follows from earlier findings that reason discloses about human nature ("the primordial natural fact[s] of freedom" and self-ownership), human action, the nature of the world around us, and the conditions under which we may flourish. The book does not discuss the nature of aggression until the third chapter of part two: "A Theory of Liberty" (chapter 8 in the book).
Readers who are eager to get on to Rothbard’s discussion of the Nonaggression Principle—which I think is better expressed as the Nonaggression Obligation—may be tempted to skip part one. To them I have three words of sage advice: Don’t do it! You will deny yourself the full benefit of this marvelous book. Read and enjoy the discussion of natural law.
For Rothbard, natural law concerns the discovery of objective values and objective ethics. He writes:
In the Thomistic tradition, natural law is ethical as well as physical law; and the instrument by which man apprehends such law is his reason — not faith, or intuition, or grace, revelation, or anything else. In the contemporary atmosphere of sharp dichotomy between natural law and reason — and especially amid the irrationalist sentiments of “conservative” thought — this cannot be underscored too often.
With obvious approval he quoted William J. Kenealy, a Jesuit priest, who wrote:
This philosophy maintains that there is in fact an objective moral order within the range of human intelligence, to which human societies are bound in conscience to conform and upon which the peace and happiness of personal, national and international life depend. [Emphasis added.]
Rothbard then asked a question posed by another natural-law philosopher, John Wild: "Why are such principles felt to be binding on me?" And he supplied Wild’s answer:
The factual needs which underlie the whole procedure are common to man. The values founded on them are universal. Hence, if I made no mistake in my tendential analysis of human nature, and if I understand myself, I must exemplify the tendency and must feel it subjectively as an imperative urge to action.
Or, Rothbard adds, as 19th-century American Unitarian minister William Ellery Channing put it, "All men have the same rational nature and the same power of conscience, and all are equally made for indefinite improvement of these divine faculties and for the happiness to be found in their virtuous use."
Much modern philosophy dismisses natural law as old-fashioned and unscientific, but Rothbard endorsed Étienne Gilson’s observation, "The natural law always buries its undertakers."