Natural law
Natural law is a philosophical concept that posits the existence of a universal "higher law" discoverable through reason, which applies to all human beings regardless of societal norms or religious teachings. This idea stands in contrast to positive law—laws created by humans that can vary significantly between cultures—and divine law, which is derived from religious doctrines and understood through revelation. Central to natural law is the belief that laws are just or morally right only if they align with this higher law. The philosophical roots of natural law trace back to ancient Greek and Roman thought, with significant contributions from medieval thinkers like Saint Thomas Aquinas. However, the modern interpretation that has influenced U.S. jurisprudence primarily stems from Enlightenment philosophers such as John Locke, who redefined the relationship between nature and human society.
Locke's theories, particularly regarding natural rights, emphasize that all individuals possess inalienable rights to life, liberty, and property. The purpose of government, according to this view, is to protect these rights, and governments derive their legitimacy from the consent of the governed. The concept of natural law has had a profound impact on American legal thought, especially as seen in the Declaration of Independence and in Supreme Court debates over the interpretation of the Constitution. Discussions surrounding natural law raise significant questions about the judiciary's role in infusing moral values into legal interpretations and the potential implications for democratic governance.
Natural law
Description: A “higher law” that, according to some political philosophers, applies to all human beings everywhere, is discoverable by reason alone, and is a standard by which to evaluate the laws made by human beings.
Relevant amendment: Ninth
Significance: Considerable debate continues regarding whether a “higher law” exists and whether the Supreme Court should rely on it in interpreting the US Constitution.
Natural law is best understood in contrast to positive law and to divine law. Positive law is that made by human beings; it may differ widely from one society to the next. Divine law is that set down in religious teachings; it often strongly influences the laws made by human beings and is said to be knowable only through revelation.
According to philosophers, natural law, unlike divine law, is knowable through the use of reason alone, via the human ability to reflect on the nature of the world and on other people. Because nature is universal, natural law is universal. It therefore stands as a body of “higher law” in relation to the laws made by human beings. According to the doctrine of natural law, positive law is just or morally right to the extent that it reflects the natural law.

Locke and Hobbes
Although the idea of natural law was first elaborated by the ancient Greeks and Romans and given its fullest premodern expression in the philosophy of the medieval philosopher Saint Thomas Aquinas, the concept of natural law that most affected US jurisprudence derives primarily from the political philosophy of John Locke. Together with other Enlightenment philosophers such as Thomas Hobbes, Samuel von Pufendorf, and Hugo Grotius, Locke transformed the classical and medieval understandings of natural law. This transformation was made possible on the basis of a fundamentally new conception of nature and its relationship to the human world of politics.
Ancient and medieval political philosophy shared the view that human beings are by nature political animals. Modern political philosophy, beginning with Niccolò Machiavelli and Hobbes, broke with this view, arguing that human beings are not naturally political. According to Hobbes, for example, life in the state of nature is “solitary, poor, nasty, brutish, and short.” In the state of nature, no sovereign exists; each person must compete against all others. Competition, scarcity, the desire for glory, and fear for one’s life make existence in the natural state terrifying. Although people are free in the state of nature to do what they desire, they cannot possibly enjoy this unlimited freedom. They have rights—natural rights—in the state of nature, but they cannot enjoy them. Therefore, they consent to form a “social compact”; they give up their unlimited freedom to be ruled in civil society so that they might enjoy a prosperous peace and comfortable self-preservation. People’s natural desire to preserve themselves is thus fulfilled in the most rational manner possible by following what Locke termed the “first and fundamental natural law.” This law commands the preservation of the society and everyone in it. Even the sovereign power that makes human laws is governed by this natural law.
Natural Law and US Law
The concept of natural law finds expression in the opening sentence of the Declaration of Independence (1776), which justifies the American Revolution in terms of an appeal to “the laws of nature and of nature’s God.” Following the philosophy of Locke, the laws of nature are transformed into natural rights: All human beings are endowed with the inalienable rights to life, liberty, property, and the pursuit of happiness, and all are equal insofar as they possess these inalienable rights. The purpose of government is to protect people’s rights, and all legitimate government is based on the consent of the governed.
The idea of a body of “higher law,” whether it takes the form of natural laws or natural rights, has been powerfully influential in US jurisprudence, particularly in the context of interpreting the vague due process and equal protection clauses of the Fourteenth Amendment. In a number of famous cases, particularly Calder v. Bull (1798) and Adamson v. California (1947), the Supreme Court debated whether there is any “higher law” or are any “principles of natural justice” that should determine how the Constitution is to be interpreted. The issue was also hotly debated in the 1991 Senate hearings to confirm Court nominee Clarence Thomas. The issue of the existence of a “higher law” raises the question of how much latitude the Court has to read substantive moral values into the Constitution. Critics of the idea of a “higher law” interpretation of the Constitution fear that such a doctrine would allow justices to read their own moral values into the Constitution and would make the judiciary too powerful in its ability to override the will of the people as expressed by their national and state governments.
Bibliography
Arkes, Hadley. Beyond the Constitution. Princeton, N.J.: Princeton University Press, 1990.
Berns, Walter. “Judicial Review and the Rights and Laws of Nature.” In The Supreme Court Review 1982, edited by Phillip Kurland, Gerhard Casper, and Dennis Hutchinson. Chicago: University of Chicago Press, 1983.
Corwin, Edward S. The “Higher Law” Background of American Constitutional Law. Ithaca, N.Y.: Cornell University Press, 1955.
Gerber, Scott. To Secure These Rights: The Declaration of Independence and Constitutional Interpretation. New York: New York University Press, 1995.
Grey, Thomas. “Do We Have an Unwritten Constitution?” Stanford Law Review 27 (1975): 703.
Locke, John. Essays on the Law of Nature. Oxford: Clarendon Press, 1954.
"Natural Law." Britannica, 4 Dec. 2024, www.britannica.com/topic/natural-law. Accessed 17 Dec. 2024.