NATURAL LAW AND THE RULE OF LAW
Joseph F.  Johnston, Jr.

The Philadelphia Society National Meeting
April 26, 2003, New Orleans

When America's founders adopted the Declaration of Independence in 1776, they based their action on certain “self-evident” truths, specifically, that men are endowed by God with inalienable rights, including the right to life, liberty and the pursuit of happiness, and that governments are instituted to secure these rights.  From the very outset of the nation, therefore, its independence was based upon the tradition of natural law, which holds that there are objective rights of liberty and property, and that these rights in turn rest upon a higher moral law.  The natural law is in sharp contrast to the opposing theory of legal positivism, which asserts that law is merely the will of the sovereign.  In the real world of today, the will of the sovereign means the power of the state.  The difference between these views of law is critical: if there is no “higher law,” then there is no conceptual basis for arguing that any human law is unjust.

We live in an age in which the public is understandably captivated by the achievements of science and technology.  Sometimes this attachment to science becomes excessive and results in attempts to apply scientific method to subjects that cannot be quantified or tested by the methods of experimental science.  One of these subjects is the law.  Ever since the late nineteenth century, a series of doctrines has appeared purporting to reduce law to an empirical or experimental discipline using, to the maximum extent possible, the methodology of science.  These efforts have proceeded under a number of labels, including legal positivism, sociological jurisprudence, legal realism and, more recently, “law and economics.”  All of these variations are “positivist” in the sense that they tend to separate law from its moral sources.

In this cultural climate, natural law appears to many lawyers to be a throwback, an obsolete category that ought to be discarded altogether.  If confronted with the term “natural law,” a practicing lawyer today is likely to say that there is no such thing, or that it is a religious notion that has no place in legal analysis.  On the other hand, if you mention “the rule of law,” he will probably indicate that he knows what this refers to, that it is a good thing and that we ought to preserve it.  And yet many if not all of the basic principles that we usually include under the rubric “rule of law” can be derived directly or indirectly from natural law sources.  Today, unfortunately, the connection between natural law and the rule of law, which formerly was so close as to amount to virtual identity, is largely neglected by the law schools and the legal profession.

This is a great shame, because the defense of the rule of law becomes much more difficult when it is unhinged from its intellectual, historical and moral roots.  As Professor Ellis Sandoz has argued in a recent paper, under the rule of law “there is an appeal to a higher standard of law and justice than the merely mortal or, at the least, than the enacted law of merely contemporary rulers.”[1]

In this paper, I first want to address a difficult semantic problem: what does the term “natural law” mean?  Then I will consider some of the ways in which traditional natural law principles have influenced what we call “the rule of law.”  Finally, I will emphasize the critical importance of the Anglo‑American common law tradition, which over many centuries has effected a unique merger of natural law principles with customary law.

One reason why natural law is such a slippery subject is that there is no easy way to define it.  If, for example, you ask a physicist and a theologian to define natural law, you will get two contradictory definitions.  The physicist will say that natural law means the scientific laws of nature (such as gravity) which act upon humans regardless of their will.  For theologians and for some traditional philosophers and legal scholars as well, natural law operates through the free will of humans and is closely identified with morality.  The “nature” in this kind of natural law does not refer to biology but to the nature of man as a free, rational and social being.  In the words of Heinrich Rommen:

The order of the world is an order of absolute necessity for unfree creatures, but it is an order of oughtness, a moral order, for rational and free beings.  In the former case the eternal law is a law of necessity; in the latter, it is a moral law of freedom.[2]

The scientific order of physical reality is separate ontologically from the moral natural law, which, as Rommen says, is an order of “oughtness.”  The human moral order derived from the free, rational and social nature of man is often supported by reference to the divine order, as in the reference to “the laws of nature and of nature's God” found in our Declaration of Independence.

As they developed, the moral and the scientific concepts of law have shared certain “law-like” goals: both seek to achieve regularity, objectivity and predictability.  In human societies, these goals are realized through such customary social habits as cooperation, trust and loyalty.  Modern scientists, however, tend to argue that these habits are explained by Darwinian natural selection.  What we call moral responsibility, biologists assert, has been naturally selected to favor behavior conducive to the survival of the organism; and every aspect of human behavior is explained by a combination of genes and environment.  The eminent biologist Jacques Monod argued three decades ago that we are entirely the product of chance and necessity.[3]  For evolutionary biologists, basic rules of law are the result of natural selection.  “The common law or any other existing body of law, if it could be traced back sufficiently far, would turn out to be directly descended from the evolved predilections for rule‑based behavior.”[4]  E.O. Wilson argues for “a purely material origin of ethics.”  Moral sentiments, like other human reactions, are products of the interaction of genes and environment.  “Ought,” Wilson concludes, “is the product of a material process.”  Even religious beliefs “can all eventually be explained as brain circuitry and deep, genetic history.”[5]  From the standpoint of evolutionary biology, “free will is an illusion, brought to us by evolution.”[6]

A persuasive case, however, can be made against the determinist hypothesis.  The science writer Matt Ridley, for example, argues that we are genetically equipped to exercise free choice.  Natural selection has placed in humans “the ability to stand up and transcend the limitations of the environment.”[7]  Our genetic inheritance, in other words, is a necessary condition of our behavior, but not a sufficient condition.  Scientific determinism cannot fully explain the action of human beings because there are limitations to the scope of science.  As the physicist Stephen Hawking has observed:

Goedel's theorem, Heisenberg's uncertainty principle, and the practical impossibility of following the evolution of even a deterministic system that becomes chaotic, form a core set of limitations to scientific knowledge that only came to be appreciated during the twentieth century.[8]

This recognition of the limitations of science validates the common-sense view that the scientific model of causation does not apply to moral discourse.  In moral reasoning, as Anthony O’Hear has argued, “the giving of intelligible reasons displaces the ultimately brute‑factish quest for causal regularities.”[9]  This capacity to give intelligible reasons for human choices is the conceptual basis for both law and morality.

I find Professor O'Hear's argument persuasive, and I believe that we are justified in using the term “natural law” in its traditional sense to refer to a system of principles for the guidance of human conduct, derived from the nature of man as a free, rational and social being, and ascertainable independently of specific positive law as enacted in any given polity.

Because man is both a rational and social being, he is able to think about the basis of his mutual relationships with others and to derive through the use of his reason the principles of human association in society.[10]  The application of reason to human conduct is the essence of the rule of law.  In the words of Aristotle, “he who bids the law rule may be deemed to bid God and Reason alone rule, but he who bids man rule adds an element of the beast ....  The law is reason unaffected by desire.”[11]

The Stoic philosophers constructed from these principles a universal system based on the concept that all men have received from nature the gift of reason, and law is right reason as applied to the regulation of human behavior.  The best-known formulation of the Stoic concept of natural law is in Cicero's Republic:

True law is right reason in agreement with nature; it is of universal application, unchanging and everlasting; it summons to duty by its commands, and averts from wrongdoing by its prohibitions ... We cannot be freed of its obligations by senate or people, and we need not look outside ourselves for an expounder or interpreter of it.”[12]

In the centuries following Cicero, the Roman jurists formulated a system of jurisprudence which, in its essential characteristics, adhered to the Stoic premise that law should correspond to natural and universal justice.  The Institutes of Justinian, published in the sixth century A.D., restated the basic principles of natural justice: “The precepts of law are these: to live honestly, not to injure anyone and to render to each person what is due.”[13]

The best-known traditional summary of natural law doctrine is found in the Summa Theologiae of St. Thomas Aquinas.  The natural law, for Aquinas, “is promulgated by the very fact that God instilled it into man's mind so as to be known by him naturally.”[14]  The natural law can be perceived by the mind without recourse to revelation, although it is strongly supported by revelation.  The most basic proposition of natural law, which for Aquinas is indemonstrable and necessarily true (“per se nota”), is that “good is to be done and promoted and evil is to be avoided.”[15] This is often called the “first principle of practical reason.”  Aquinas, following Aristotle, argues from a teleological perspective: the good is a natural end or goal of mankind, which is to be pursued for its own sake.  Under the category of the naturally good, Aquinas emphasizes certain natural inclinations of man, including the inclination to preserve human life, to educate one's offspring, to live in society and to avoid offending those among whom we have to live.  The norms derived from these inclinations conform to man’s rational nature and are implicit in the human social order.

To summarize, the concept of “nature” in traditional natural law theory does not refer to materialistic biology but “to the rational nature of each individual man [and] to man's endowments of intellect and free will, on which rest the dignity, liberty, and initiative of the individual person;....”[16]

For man, as a free, rational and social creature, the order of being becomes an order of “oughtness” – a moral order.  As St. Paul said, what the divine law requires of all men is “written on their hearts.”[17]  The word “natural” is thus prescriptive and not merely descriptive.  The Latin word “naturalis” suggests a necessary condition or presupposition of social order.  The function of law is to establish and preserve a just, predictable and stable order of human relationships.  Human society depends upon the recognition of basic principles of possession, reciprocity and obligation.  From these requirements can be derived a number of general principles that form the basis for contractual and other obligations.  “Thus there is a naturalis possessio at the root of all property.  There is a naturalis obligatio, which may or may not be legally protected, but which is the necessary prerequisite of all obligations.”[18]  It is here that we can see the essential link between natural law and the rule of law.

As critics of natural law theory have often pointed out, the natural law position requires some basic assumptions which are difficult or impossible to prove empirically.  These include the assumptions that human life has intrinsic value; that humans are capable of free moral choice; that there is an intelligible “order of oughtness” that is discoverable by human reason; and that human beings have a natural desire to maintain an orderly society.[19]

The recognition that certain fundamental assumptions are unproven, however, should not surprise or discourage anyone.  Every organized field of human knowledge is based on unproven assumptions.  Science itself accepts the intelligibility of the world but cannot explain it.  Moreover, science rests upon the logical laws of identity and contradiction and, in addition, is dependent upon measurability and mathematical formulation.  Mathematics, which is essential to the very existence of science, is a non-material, conceptual scheme that cannot itself be “proved.”[20]  Scientists cannot avoid using such terms as order, form, structure, equivalence, simplicity, coherence and elegance to describe their view of the world, but these are ideal, nonempirical concepts.  They represent metaphysical assumptions that underlie the scientific enterprise, just as the principles inherent in the moral and social order underlie the natural law.

Based on the assumptions previously discussed – that human life has intrinsic value; that humans are capable of free moral choice; that there is an intelligible “order of oughtness”; and that humans have a natural desire to live in an orderly society – we can infer certain principles that bring us closer to the “rule of law.”  The following principles are not intended to be exclusive, but are among the most important.

1.  The protection, preservation and procreation of human life.  The prohibition against murder, the right of self-defense and the obligation to care for children follow from the principle that human life has intrinsic value.  The value and dignity of the human person are also supported by the Christian doctrine that man has a special place in the divine order.

2.  Individual liberty.  The Roman jurists assumed that personal freedom was a part of natural law.  Ulpian, writing in the second century A.D., states that “by the law of nature all men are born free.”[21]  The natural law concept of liberty was brought into English constitutional law principally by chapter 39 of Magna Carta, which established that no free man shall be imprisoned except by the law of the land (later called “due process of law”).  By the time of Bracton (thirteenth century), Magna Carta was known as a charter of “common liberties” or a “constitutio libertatis.”  In modern natural law theory, personal liberty is a necessary condition of the natural desire to pursue one's own goals, subject to the qualification that the similar liberty of others is to be given equal respect.  “It is not ...  contrary to the nature of society to look out for oneself and advance one's own interests, provided the rights of others are not infringed; ....”[22]

3.  Protection of property.  Liberty and property have often been linked together, since both are essential to the advancement of man’s proper goals in society.[23]  Most natural law writers argue that, because private property is essential to social peace and good order, the right to own property is a part of natural law.[24]  Without property, the individual would be wholly dependent on others and therefore could not be free in any meaningful sense.  “The institution of private property is of natural law.  In the long run man cannot exist, cannot make good his right to marriage or to a family or to security of life, and cannot maintain his sphere of individual right to a life of his own, unless he is entitled to ownership through the acquisition of goods.”[25]  Richard Weaver argued that, in a society he saw as culturally and morally decadent, “the right of private property... is, in fact, the last metaphysical right remaining to us.”[26]  Weaver deemed this right “metaphysical” because property reflects the deep and essential relationship between man and the part of the world around him that is his own.

4.  Reciprocity.  Reciprocity is the conceptual basis for the natural law principle that “promises should be kept” (pacta sunt servanda), which in turn is the basis for the law of contracts.[27]  All known societies have customary rules of promise making and promise keeping.  Reciprocity follows from the Aristotelian principal, “give to each his due,” which was one of the cornerstones of natural justice set forth in the Institutes of Justinian (Sixth Century A.D.).

5.  Injure No One.  This principle of natural law is the basis of the law of torts.  It gives rise to the principle of restitution for harm done.  “Among those Duties we account Absolute, or those of every Man towards every Man, this has the first Place, that one do no Wrong to the Other;.... hence it follows, That if any Harm or Damage be done to another, he who is truly chargeable as Author of the Wrong, ought, as far as in him lies, to make Reparation…”:[28]

6.  Trust (fidelity).  The obligation of trust or fidelity is a necessary condition of social harmony.  The loyalty required of a trustee or other fiduciary is set forth in the Biblical precept that “no man can serve two masters.”[29]  It is at the heart of the law of trusts, agency, partnerships and all other arrangements involving fiduciary obligations, in which one person is entrusted with control over some aspect of the life or property of another.[30]  Fiduciary obligations have been invoked by courts of equity for centuries.  The duties of loyalty and care expected of trustees, corporate directors and other fiduciaries are derived from natural law principles and reflect the institutionalization of trust that is essential to the survival of human associations.  Because of its universal applicability, the moral principle of trust should be considered a principle of natural law.

It is obvious that the foregoing principles of natural justice are quite general.  All of them, in practice, are necessarily surrounded by multiple exceptions and conditions required by actual circumstances.  It has often been noted by critics of natural law that the more specific the principles become, the more readily they are subject to challenge.  It is for this reason that natural law principles, in order to be given effect, must be embedded in the actual customs and practices of a given society.  In Anglo-American law, this means the common law tradition, as modified by acts of Parliament representing the “public policy” of the community.  As Corwin indicates, “the notion that the common law embodied right reason furnished from the fourteenth century its chief claim to be regarded as higher law.”[31]  The lengthy history of “embedding” the natural law in the common law gives us the rule of law operating as a real practice and not just an abstraction.  Moreover, because of its insistence that the ruler is subject to the law, the common law provides a powerful defense of individual freedom against the state.

For the sake of simplicity, I use the term “common law” to include the equitable principles traditionally applied by the Chancery Courts in England and America.  Equity applies “where the principles of law, by which the ordinary courts are guided, give no right, but upon the principles of universal justice the interference of the judicial power is necessary to prevent a wrong, and the positive law is silent.”[32]  The influence of the natural moral law is apparent in the well-known principles of equity, such as the doctrines of equitable rescission, unconscionability, estoppel, “entire fairness” in fiduciary dealings, and the equitable maxim that no one may profit from his own wrongdoing.

In addition to the substantive principles that can be inferred from natural law, there are “process” requirements that are equally basic.  By the “legal process” I mean both the formal requirements of an enactment that make it part of a system of “law,” and the procedural requirements of adjudication that satisfy “due process of law.”  These two aspects of the legal process are closely interrelated.

The natural law tradition, in contrast to the positivist principle of the will of the sovereign, holds that legal systems possess certain intrinsic elements that distinguish genuine law from arbitrary commands and decrees.  The most basic of these elements are regularity and predictability, which enable the citizens to guide their conduct.  Other more specific requirements of natural legality were summarized by Professor Lon Fuller in his important book, The Morality of Law (1969).  Based in part on his experience with the Nazi legal “system” at the Nuremberg trials, Fuller claimed that there were certain requirements that must be met by any legislation as necessary conditions of legality.  These requirements, which he called the “internal morality of law,” were as follows: the non-retroactivity of rules; the ability of those subject to the rules to comply with them; public promulgation; coherence of the laws with one another; intelligibility; sufficient constancy over time so that people can rationally order their conduct; generality (so as to avoid bills of attainder and other legislative acts which are really judicial sentences operating on individuals, thereby depriving them of the procedural rights of due process); and administration of the laws in a manner congruent with their wording.[33]  These characteristics have deep roots in the natural law tradition and in the history of the English common law.  One can quarrel with one or more of Fuller's requirements of legality, but any political system that departed drastically from Fuller's rules of internal morality could not fairly be called lawful.

We then move to the level of adjudication.  The requirements of regularity and predictibility apply here too.  The existence of legislation meeting the formal requirements of law does not ensure that the law will be fairly applied in actual cases; regular adjudicative procedures are also needed.  These procedures are based not solely on abstract reason but emerge out of long experience.  In the Anglo-American common law, they are reflected in a series of precedents going back to Magna Carta, supported by the legal writings of Bracton, Fortescue, Coke, Blackstone and many others.

The most basic of these adjudicative principles is the necessity for adequate notice and opportunity to be heard in one's defense.  This principle has for centuries been closely identified with Chapter 39 of Magna Carta, providing that the Crown will not proceed against any free man “except by the lawful judgment of his peers and by the law of the land.”  As Professor A.E. Dick Howard persuasively argues, “the principle of procedural fairness, above all, of notice and opportunity to be heard in one's defense, born of Magna Carta and nurtured through centuries of English and American cases, remains one of the cherished presuppositions of our system of justice.”[34]  The notion of “due process of law” is among the “higher law” principles incorporated into the Bill of Rights in our Constitution (see Amendments V and VI).

At all times in its history, America's economic strength and political health have depended upon adherence to the rule of law, a set of institutionalized principles designed to defend the individual against invasions of person and property and to provide a mechanism for the fair adjudication of disputes.  This structure of rules is based on the permanent principles of the moral order and on long-standing custom.  The rule of law as developed in England and America is not merely the abstract “right reason” invoked by Cicero and the Stoics, and deemed to be universal and unalterable.  Instead, the Anglo-American rule of law has been achieved through a centuries-long series of fierce and often bloody conflicts, from the revolt of the barons against King John to the Glorious Revolution in England and the American Revolution.  The principles of natural law are available to all, but each society traces the path from despotism to liberty through its own history, customs and struggles.[35]  Examples of these hard-won principles, now considered axioms of the rule of law, are the independent tenure of judges, habeas corpus and the doctrine that the rulers are subject to the law.

It is therefore wrong to assume that the rule of law can be explained by Lockean or other contractarian doctrines that fail to take into account the lengthy historical process in which the rational principles of natural law have become embedded in the real experience of the English people and their successors.  It is equally misguided to assume that this tradition can simply be transferred wholesale to other societies with vastly different cultural histories.

The United States is a republic based on the rule of law.  But, as Benjamin Franklin might have asked, can we keep it?  We are fortunate that the rights of speech and property are better protected in this country than in most others.  On the other hand, we are enveloped in a heavy fog of constantly changing legislation, codes, rules and regulations, administered by swarms of bureaucrats sent “to harrass our People, and eat out their Substance”.[36]

We are burdened by an out-of-control litigation system that bankrupts entire industries primarily for the benefit of lawyers.[37]  In constitutional adjudication, the founding document is too often construed by the Supreme Court in accordance with the ideological predilection of judges rather than the intent of those who wrote and ratified it.  If we look at Lon Fuller's indicia of lawfulness, it is obvious that something has gone badly wrong.  Take, for example, the requirement that laws be intelligible, coherent, general and constant over time (enabling people to conform their conduct to the rules).  How clear and coherent is the Internal Revenue Code?  How easy is it for the citizens to plan their conduct in accordance with the Byzantine body of “law” that surrounds us?

Intellectual history moves in cycles, in the legal profession as elsewhere.  If we are to realize the moral strength and political wisdom of which our nation is capable, we need to turn the cycle of ideas back toward first principles.  This means the rediscovery of the tradition of natural law, which can still be dimly perceived through the obscurity of our overloaded legal system.  The current revival of natural law theory gives us an opportunity to reinvigorate a great tradition and restore an essential framework for the rule of law.