Natural Law and Human Nature in “The Ethics of Liberty”

Kuznicki discusses Murray Rothbard’s arguments about the state of nature and the nature of man.

Jason Kuznicki

Jason Kuznicki was a senior fellow and the editor of Cato Books and of Cato Unbound, the Cato Institute’s online journal of debate. His first book, Technology and the End of Authority: What Is Government For? (Palgrave, 2017) surveys western political theory from a libertarian perspective. Kuznicki was an assistant editor of the Encyclopedia of Libertarianism. He also contributed a chapter to libertarianism.org’s Visions of Liberty. He earned a PhD in history from Johns Hopkins University in 2005, where his work was offered both a Fulbright Fellowship and a Chateaubriand Prize.

Chapters 1 and 2 of Murray Rothbard’s The Ethics of Liberty are about man’s nature. Rothbard writes:

In natural-​law philosophy… reason is not bound, as it is in modern post-​Humean philosophy, to be a mere slave to the passions, confined to cranking out the discovery of the means to arbitrarily chosen ends. For the ends themselves are selected by the use of reason; and “right reason” dictates to man his proper ends as well as the means for their attainment. (p 7)

The good is the fulfillment of man’s potential, with man understood to be the rational animal-​-​the one who survives and flourishes based on the use of reason and its application to the problems that confront him. The good life is a reasoned, examined life; evil consists of neglecting or denying reason, or of thwarting it in the self or others.

Many, of course, deny that mankind has a nature. The implication here is obvious: without a nature, all claims of a normative natural law would be void. The problem with such denials, as Rothbard notes, is that their proponents so often end either by contradicting themselves or by employing something suspiciously like natural law anyway.

I found Rothbard a bit laconic on this point, but I think I see where he was headed. The trouble with denying that man has a nature is that it runs into problems in the area known as argumentation ethics: The act of advancing an argument is a speech act that all by itself implies that the arguer believes certain things. If the content of the argument contradicts these things, the arguer has a problem.

Suppose some creature asserts that man has no nature. We need not and possibly should not call this creature a man, because his own theory suggests that he can’t be an instance of a type that doesn’t exist.

It might not be unreasonable to ask him, though, why he believes that “man” has no nature. And when the creature offers propositions in support of his conclusion, we readily recognize that he has attempted what philosophers call an argument. Perhaps sadly for him, we are also forced to conclude that he is a member of mankind after all. His argument to the contrary is self-​defeating.

That’s because argument is a thing that man-​-​the rational animal-​-​does pretty well, and that nothing else does particularly well at all. Even offering a flawed argument isn’t the sort of thing we expect from puppies or toasters. (In my experience, people who say that computers can argue have not usually spent much time around the ones that purport to do so.)

The act of arguing even semi-​cogently against the existence of human nature is itself a manifestation of the thing that the argument attempts to deny. And the act of proposing this argument to the rest of us would be nonsensical without an expectation that we might evaluate it-​-​favorably, the arguer hopes-​-​according to standards of rationality congruent with those found in the arguer’s own mind.

If we can do that, we would appear to share a nature, an essential point of commonality that motivates us in similar ways. Man’s nature is to reason about the world, whether well or badly, and to act according to the plans his reason suggests.

The next topic in The Ethics of Liberty is self-​ownership, which also forms a part of man’s nature. I’ll cover it in the next post in this series.