Natural Law

Natural law consists of one supreme and universal principle from which are derived all our natural moral obligations or duties. Through the exercise of their reason human beings can discover the natural laws governing their behaviour – can discover how morally they ought to live and behave. They have free will, they can choose whether or not to live and behave that way (1) . Natural law is an ambiguous term most commonly associated with the field of philosophy and defined as the unwritten law derived from nature and applicable to all humankind regardless of culture or customs (2). Natural law exists in opposition to positive law , which is composed of the formal rules developed by individuals and enforced within a society. The term is ambiguous because throughout history natural law has been studied by diverse scholars and utilized within numerous fields of study.

Many ancient Greek philosophers believed all humans possess the faculty of choice and freewill. The Stoics believed the universe was governed by an eternal law rooted in reason. The stoic doctrine is divided into three parts: logic, physics and ethics. The notion of morality is stern, involving a life in accordance with nature controlled by virtue. Aristotle was schooled in these principles and it certainly helped shaped his work in the area of ethics. Stoic ethical teaching are based upon two principles: the universe is governed by absolute law - which admits of no exceptions and that the essential nature of humans' is reason. It is their belief that all human beings should "live according to nature" (3). They supported Aristotle’s (384-322BC) belief that an action which is “just by nature” is not necessarily “just by law.” The Stoics believed a positive law that is in violation of nature is not a true law (4).

Marcus Tullius Cicero (106-43BC), a Roman statesman and political theorist, is considered the architect of natural law theory. It was the stoic teachings that helped lead Cicero to his theories about Natural Law. He believed that philosophy teaches us that by nature human beings have reason, that reason enables us to discover the principles of justice and that justice gives us law. Therefore any valid law is rooted in nature and any law not rooted in nature (such as a law made by a tyrant) is no law at all. He stated that the most divine life was one lived according to reason, not according to the search for pleasure (5). It is believed Cicero successfully argued before a Roman court on this point and was able to convince his audience that elements of Rome's positive law were unlawful because they contradicted natural law (6).

Throughout history natural law has been the subject of persistent controversy. Scholars continue to disagree about both the definition of the term, and the relationship between natural law moral theory and natural law legal theory. St. Thomas Aquinas (1225–1274) recognized the overlap between natural law moral theory and natural law legal theory. Aquinas advocated that all humans are born with a “vacuous imperative” to do good and avoid evil. He stressed these conflicting virtues necessitate laws promulgated by humans. He believed that all the rational being should concern themselves with was the Eternal Law, the eternal law is God's wisdom and like the rest of creation, man is destined by God to an end and receives from Him a direction towards this end (7). Aquinas also dicussed the three constituents in his work the Summa Theologica ; discrimination norm, binding norm and manifesting norm. The discriminating norm is human nature itself, the binding norm is the Divine authority, imposing upon the rational creature the obligation of living conformity with his nature and the manifesting norm which determines the moral quality of actions. He believed that rational beings will perceive what is the moral constituation of our nature, what kind of action it calls for and whether a particular action possesses this requisite character (8).

During the 17th century Hugo Grotius (1583–1645), a Dutch philosopher and lawyer, developed the first comprehensive theory of international law based on his adaption of natural law. Grotius argued that humans are rational and reasonable by nature. He suggested rules which are natural and dictated by reason facilitate harmony (9).

Thomas Hobbes (1588–1679) questioned the authenticity of natural law. He stated life is “poor, solitary, nasty, brutish, and short” and that individuals are unqualified to determine what is right and what is wrong. The English philosopher argued that the commonwealth is entitled to both unlimited power and rights (10). Hobbes believed a substandard system of justice was the byproduct of natural law. He argued empowering the commonwealth was the only way to ensure liberty was secured.

John Locke (1632–1704) advanced understanding of natural law by emphasizing the concept of human nature and one’s natural right to both self defense and privacy. The Christian advocate believed natural law was in accordance with the will of God because human nature and the world are reflections of God’s will (11).

Hobbes and Locke used the idea that Natural Law needs a basis for the claim that at least some moral standards are in some sense objectively and universally valid and that these can be discovered by engaging in moral reasoning. Social contract theory attempts to provide such a basis, it attempts to derive morality from prudence.The Social Contract theory states that we must views law and society as products of an actual (or hypothetical) social contract among rational self-interested individuals. It only then human beings can use rational thought and reason to make ethical choices (12).

While the philosophies of Immanuel Kant(1724–1804) and Jeremy Bentham (1748–1832) detracted from the notion that nature provided an adequate source of moral and legal norms, the 19th century ushered a renewed interest in the theory. These men did not believe in the Divine Command theory or Natural Law as they believe all actions public and private are open to evaluation on the basis of their utility (13). Bentham believed that nature has placed mankind under the governance of two sovereign maters, pain and pleasure. It is for them alone to point out what we ought to do, as well as to determine what we shall do (14).

The reign of Adolf Hitler (1889-1945) initiated mass questioning surrounding the validity of positive law. Martin Luther King (1929-1968) also generated interest in natural law when he argued the merits of Aquinas’ theory. King argued a manmade law is only just if it is in harmony with God’s law (15).

Natural law theory has also been utilized within the political arena and has made a lasting and important impact in many political leaders Thomas Jefferson (1743-1826) used elements of natural law theory in his justification for introducing the United States Declaration of Independence. Thomas Jefferson, declaring independence from British tyranny, appealed to the “laws of nature and of nature’s God.” The laws, which he held to be self-evident and were largely based on Locke’s theories (16). Martin Luther King Jr. – writing as a Baptist preacher from a jail in Birmingham, Alabama claimed that an “unjust law is no law at all” and defined an unjust law as “a human, law that is not rooted in eternal and natural law – he based his words on work of Aquinas. The Universal Declaration of Human Rights was also based on natural law theory (17). The theory is also credited with providing the framework for the development of English common law (18).

As society continues to evaluate what actions are in agreement with natural law, contentious issues such as homosexuality, medical research and the death penalty are argued against the merits of the theory. It would seem Aquinas was correct in his belief that natural law will forever remain in a state of flux. Continuously evolving and reforming.

(1) , (13) Waluchow, Wilfrid, J. (2003). The Dimensions of Ethics: An Introduction to Ethical Theory. Toronto: Broadview Press.
(2), (10) Guerra, M. (2005). The Limits of Darwinian Natural Law. Perspectives on Political Science, 34.3, p. 144.
(3), (5), (6) Clayton, Edward. (2006). Cicero (c. 106 - 43 B.C.). The Internet Encyclopedia of Philosophy. Retrieved October 1 2009, from
(4) Bovard, J. (1988, Spring). The World Bank vs. the World’s Poor. The Freeman: 184–186.
(7), (8) Fox, J. (1910). Natural Law. The Catholic Encyclopedia. Robert Appleton Company: New York.
(9) Ellickson, R. (1991). Order without Law, how Neighbors Settle Disputes. Harvard University Press.

(11), (17) Dolhenty, J. (n.d.). An Overview of Natural Law Theory. Retrieved September 22, 2008, from
(14) Bentham, Jeremy. (1843). The Works of Jeremy Bentham, edited by John Bowring.
(15) Strauss, L. (1983). On Natural Law. Studies of Platonic Political Philosophy. University of Chicago Press, p. 140.
(16) George, P, Robert. (1994). The Natural Law Theory:Contemporary Essasys. Clarendon Press: Oxford.
(18) Donald, J. (n.d.). Natural Law and Natural Rights. Retrieved September 22, 2008, from