Rule of Law: The Story of Human Rights in World History
2004 ORIAS Summer Teachers' Institute 
July 26-30

What is Natural Law: Antiquity :*

Introduction to the concept of Natural law and its development from the Sophists to the Justinian Code.

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Natural law (Naturalism, jus naturale) is an excellent example of a simple-sounding concept whose definition has become obscured by the many meanings attributed to it.

Though it obviously relates to the law as seen in nature, of course, definitions of nature have varied since the term "natural law" was introduced by Aristotle (384-322 BCE) in his Nicomachaen Ethics. As its subsequent discussion by the Stoics and the Romans, by the Byzantine Justinian Code, by religious scholars throughout the Middle Ages, by Enlightenment thinkers as well as contemporary legal scholars shows, Natural law is a Western concept that has formed an important pole (against Positivism) in debates about the origins of law.

Natural law, then, can perhaps most simply be defined as what it is not, that is positive law, or law given by a government to its people.

Natural Law in the Ancient world

The Sophists argued that no one could violate the laws of nature, which showed (in humans as in animals) that the weak should be dominated by the strong. Natural law was that "might made right."

In his Republic, Plato (429-348 BCE) argued that natural inclinations and capacities should order the ideal society. Men made of "gold" should lead as philosopher-kings, while those of meaner metals should work as craftsmen or farmers. Children should be classified early and raised by the class fitting of their potential. In this "natural" ordering of society, "a man should do his work in the station of life to which he was called by his capacities."

Aristotle, in Nicomachean Ethics, distinguished between natural law and conventional law, the former being an enduring universal truth, the later a temporary rule. This distinction is preserved today in the opposition of natural law to positivism.

The Greek Stoics viewed Natural law in a similar light, as a ruling principle based on universal reason. They believed that this inherent rationality in the universe was created by God, whose law applied universally and equally.

Cicero (106-43 BCE), an influential Roman jurist, was heavily influenced by the Stoics in his understanding of natural law, which he described by writing that "True law is right reason in agreement with nature." It is universal ("There will not be different laws at Rome and at Athens or different laws now and in the future, but one eternal and unchangeable law will be valid for all nations and all times"), divinely-inspired, and divinely-enforced. Law is not necessarily just, but justice is inherent in nature.

Roman jurists gave Natural law a number of different meanings, many of which are present in the Justinian Code. Among them are the following:

  1. normal and reasonable behavior in society
  2. the law that arises universally in behavior among nations, jus gentium
  3. the law in nature among animals (natural coupling of male and female for procreation)

It is worth noting that the Stoic idea of equal application of Natural law lead many to view slavery as "unnatural." The Justinian Code makes the seemingly anachronistic comment that "Slavery is an institution of the jus gentium by which, contrary to nature, one man is made the property of another."**

Different ideas about "Natural law" existed in the ancient world. What were they?

1. Natural law is what is seen in nature, among animals. (Sophists)
2. Natural law is what is natural, ie, what is universal and enduring through time. (Aristotle)
3. Natural law is based on reason, perhaps given by God. (Stoics, Cicero).
4. Natural law is what is in society, either in one country or among nations.
5. Natural law is what is in nature/animals.

Find the different ways that Natural law is applied in the Justinian Code.


*Adapted from Edgar Bodenheimer. Jurisprudence: The Philosophy and Method of the Law. Cambridge, MA: Harvard University Press, 1962 by Hallie Fader, ORIAS, July 2004. Bodenheimer focuses exclusively on the "Western tradition" of law, namely the development of Common law and Code law in Europe and North America. While simplifying his development of legal philosophy to focus on natural law, I have relied on his chronology and analysis of legal philosophers for this account.

**Bodenheimer also notes that the Stoic view of Natural law as a universal for all peoples and nations may have benefited from its political expediency during the period of Imperium Romanum.

What is Natural Law: The Middle Ages through the Enlightenment: Continuation of the development of Natural law to the 18th century.

page created by Hallie Fader, ORIAS, July 2004.

Sponsored by the University of California at Berkeley Office of Resources for International and Area Studies (ORIAS), Institute of East Asian Studies, Center for Latin American Studies, Center for Middle Eastern Studies, Institute of Slavic, East European and Eurasian Studies, Center for South Asia Studies, Center for Southeast Asia Studies, Institute of European Studies. 

Funding is provided by Title VI grants from the United States Department of Education.