§ 1. There are many definitions of laws, which can easily be defended but much more easily attacked. For nothing is rarer than an exact definition. Indeed, every difficulty can be reduced to a definition.
Aristotle, To Alexander: Καὶ γὰρ ὁ νόμος ἐστίν, λόγος ὡρισμένος καθ᾽ ὁμολογίαν κοινὴν πόλεως, μηνύων πῶς δεῖ πράττειν ἕκαστα. For law too is a statement—or rational ordinance—defined by the common consent of the city, showing how each thing is to be done.
Cicero, book 1 of On the Laws: “Law is the highest reason implanted in nature, which commands those things that ought to be done and forbids their contraries.” And in book 2 of On the Nature of the Gods: “Law is the prescription of what is right and the repulsion of what is depraved.”
St. Thomas, I–II, question 91, article 4: “Law is an ordinance of reason for the common good, promulgated by him who has care of the community.”
Papinian, Lex est, π. On Laws: “Law is a common precept, the considered judgment of prudent men, the coercion of offenses committed either willingly or through ignorance, and, finally, the common pledge of the state.”
Alfonso de Castro: “Law is the right will of him who represents the people, promulgated by voice or writing, with the intention of obliging subjects to it.”
Valencia: “Law is a certain right decree of practical reason, sufficiently sanctioned by him who bears the care of the community, and established so that by its force some mode must necessarily be applied, whether in a thing or in an action, for the sake of the common good.”
John de Salas: “Law is a precept imposed upon a community, perpetually binding unless it is revoked.”
Suárez, book 1, chapter 12: “Law is a common, just, and stable precept, sufficiently promulgated.”
I willingly pass over other definitions, such as: “A law is a general command of the people or of the plebs, upon the senate’s proposal.” Gellius, book 10, chapter 20. And:
“A law is what the Roman people established when questioned by a senatorial magistrate, such as a consul.” For these contain particular law.
Most of those definitions seem to me capable, by a suitable interpretation, of being referred to a true understanding and explanation.
Therefore, in order that we may place the thing itself before our eyes, many matters must be considered in the meaning of laws and in the thing itself.
§ 2. First, the Hebrews call law תורה, from תור, which means to explore, consider, and order. For תור is order, method, ordinance; for an investigation proceeds in a most orderly manner when it prudently examines a matter. At Esther 2:12 it designates a time or order. But I prefer to derive it from ירה, which means to teach; and among the Hebrews it is taken very broadly, so as to mean method, doctrine, disposition, judgment, and statute. Among the Greeks it is called νόμος, not so much from feeding as from distributing to each person his own right. Formerly, however, they called songs νόμους, as Aristotle is the authority, Problems, section 19, problem 28: “Why are most laws called songs? Is it because, before human beings knew letters, they sang their laws, lest they consign them to oblivion—a practice which even in our own age is customary among the Agathyrsi? Therefore they also called the earliest of the later songs by the same name by which all the earlier ones were called.” Law, therefore, is called a measure, rule, norm, condition, and precept, even when inequitable; but we are speaking of law in its proper sense.
§ 3. Next, every law is composed of various parts. For in it there is a judgment, or an act of the legislator’s intellect, by which he judges that something is to be done or not done and that the subject is to be bound. Next there is a decree, or an act of the will, by which he determines to bind him. Third, there is promulgation, by which the law is made known to the subject. Fourth, there is the subject’s understanding, by which he recognizes his obligation—or, certainly, fails to know it through his own fault. Finally, there is the thing itself, or what they call the object, about which the judgment and will both of the legislator and of the subjects are occupied. The law in Paradise is: “You shall not eat from the tree of the knowledge of good and evil.” This object, known by God and human beings, is called law and is the terminus of divine command and human obedience. For it directs both the intellect and the will of the human being. First God understands that this is to be commanded; next he wills to command it; and finally he declares it by his command, upon knowledge of which the obligation to obey arises. Therefore, the matters disputed at greater length here by the theologians—whether law is a work of the intellect or of the will—are in no way necessary for us, since it embraces both. Once these matters have been established, therefore, it is easy to comprehend the nature of law in a brief definition.
Law is an equitable precept of a superior, obliging a subject to act or not to act. For precept is the genus; equity excludes unjust commands, which are called laws only by an abuse; and the obligation of the subject includes promulgation and the other elements. I shall speak in its proper place about stability and the other attributes of laws.
§ 4. There is a great affinity between law and right, and they are frequently confused. Ius, right, is so called because it is just, and it is the object of justice. For that virtue establishes its own object, just as the other virtues do. For they say that this is right which has flowed from justice as its fountain. General right, I say, is that which corresponds to general justice: namely, that which in every thing and action is consonant with right reason and equity. Particular right is that which corresponds to justice strictly taken, and it is either what law prescribes or the faculty which law grants to each person. In the usage of jurists, ius frequently signifies law. “Right is civil equity,” says Crispus, “either sanctioned by written laws or received in institutions or customs.” And these are the beginnings and the nature of laws.
§ 5. The division of laws and of right is, by a certain proportion, the same. The ministers of Themis themselves establish a varied partition of right. They call the natural inclination of each thing primary natural right; next, secondary natural right, such as standing by promises and harming no one. This same thing is called by some primary law of nations. Third, what is derived from this they call secondary law of nations, as that which is gathered by practical reasoning in a manner so consonant with nature that all nations—or nearly all, unless they are exceedingly savage—agree upon it. Thus natural right is not altogether distinct from the law of nations. For the emperor calls that the law of nations which natural reason has established among all human beings. Necessity establishes secondary natural right, as Aristotle says in book 1 of the Politics, chapter 3. An example is servitude, which is not contrary to natural right—namely, that milder servitude amended by Justinian and others; for the ancient form was altogether barbarous and tyrannical.
They likewise call right that of τῶν νόμων ἐγγράφων, written laws, and ἀγράφων, unwritten laws; others call them θέσμια, ordinances, and τὸ νόμιμον, what is lawful. There is also the right of persons, things, and actions.
From this also arose what is called civil law, which neither departs wholly from natural right or the law of nations nor serves it in every respect. Thus, when we add something to or subtract something from the common right, we understand it as proper or civil law. But if it departs altogether from natural right, it is no longer right, but injustice and tyranny.
Thus servitude belongs to the law of nations. For although all are born free—because the whole human race is one and from one—nevertheless they can become slaves by the law of nations, which is not contrary to the law of nature. For he who brings an unjust war against another and contrives his death can himself be killed:
In my judgment, guile is permitted to repel guile, And laws allow arms to be taken up against the armed.
Nevertheless, by the humanity of civilized nations, servitude was substituted for the penalty of death. Civil law, therefore, never corrupts natural equity, but determines it. But if at times it seems to depart rather far from it, it must nevertheless have a reason which, on account of some circumstance, makes what is prescribed just. It certainly seems harsh that by prescription one should lose possession of one’s own property; but lest the ownership of things be tossed into uncertainty for a very long time when the possessor is uncertain, it is more prudent to provide for public tranquility at the cost of a few. Gregory of Toulouse speaks excellently in the Syntagma of Law, book 11, chapter 1, § 9 and following: “In the same way, civil reason too has natural reason almost always as its companion. For a reason can scarcely be named which is not natural; yet it does not always consider what accords with the common nature of all, but sometimes only the circumstance of a particular civil society, so that someone’s life may be ordered more suitably, account being taken of the customs of the present place and of what happens there more frequently than elsewhere among human beings generally.”
Hence civil law—which is proper to each city, that is, which is especially conformed to the rites and customs received in the city—partly agrees with the law of nature, as though with the leaven of equity, justice, and right, from which it has so much as is just; yet it does not serve it in every respect—that is, it does not enact altogether according to universal natural equity. For the necessity of societies sometimes commands a departure from that equity: penalties may be increased because of the frequency of crimes, or harsher provisions enacted because customs are more savage and barbarous; at other times penalties may be diminished for the contrary reason. It is expedient to temper laws in one way here and in another way elsewhere. All these laws, although different and contrary in different places, are nevertheless just and equitable, but by a different rationale and in a qualified sense—not according to the general consideration of the law of nature in the abstract, but according to natural right in the concrete, that is, according to the suitability of the subject for whom the legislator prescribes what is just. Thus I do not doubt that natural right also exists in civil law. Yet in that concrete case the designation civil predominates. And although civil sanctions, if they are not consonant with reason, do not make right, even though they are so named, but rather corruption; nevertheless, if they agree with reason, since that reason is natural, civil law will in this way also be natural law, and in the concrete it can be called both natural and civil law, by reason of its restriction to this or that city.
§ 6. These are the determinations they have made concerning right; the division of laws also is not dissimilar. In the Timaeus, Plato divides law into divine, celestial, natural, and human. He distinguishes celestial law from divine. He calls that divine which theologians call eternal law, which is the rational order existing in the divine mind and governing the universe. For Plato, celestial law is μοῖρα, or fate, which Christian piety does not admit except under a sound interpretation. Natural law is that which we defined above. St. Thomas divides law according to the same rationale into eternal, natural, divine, and human; others divide law or right into natural and positive. Jurists consider natural law, the law of nations, and civil law; they leave divine and canon law to theologians. Authors divide civil right or law into six parts.
For a law is what the Roman people established when questioned by a senatorial magistrate. But this definition concerns only Roman law and the law of the state while it stood. For Romulus had established that nothing should be sacrosanct unless the plebs or people had sanctioned it. What had seemed good to the curiae was referred to the senate. For the enactment of laws, the creation of magistrates, and the determination of war were in the power of the people. Indeed, the imposition of a more serious fine was also decreed by the people, Titus Livy, book 25.
A decree of the senate is what the senate determined. If any tribune interposed his veto, only a formal opinion was written down and the matter was referred to the senate and people. Many, however, exclude this kind of law; for decrees of the senate and magistrates did not possess the same force as commands of the people, since both magistrates and plebs swore to a law. Nevertheless, it can be called a true law; for lesser power or obligation does not cause it to cease being law, but causes it to be a weaker law, nor does it belong to the definition of law that subjects swear to it. For the senate is consulted in the place of the whole people, and therefore it possesses power over affairs to be conducted, except those which the people reserved.
Festus defines plebiscites as those measures which the plebs accepted in the tribal assemblies, without the Fathers, upon the proposal of a plebeian magistrate—that is, a tribune of the plebs.
Edicts were the measures which the other magistrates—such as consuls, aediles, and tribunes, but especially praetors—promulgated at the beginning of their assumption of office. For this reason it was called praetorian law, just as it was also called honorary law, because it had been declared by those who held honors.
At the beginning of their term the praetors declared what law they would pronounce concerning each matter, so that each person might prepare himself: book 2, § 5, On the Ancient Civil Law of the Romans, and Sigonius, book 3, chapter 5. In book 1 of the second pleading Against Verres, Cicero calls it an annual law. For the Kalends of January brought it to an end, and on the same Kalends its beginning arose. By this law the urban praetor pronounced judgment, not according to his own discretion, but in accordance with laws already enacted; for he assisted, supplemented, and sometimes corrected the laws of the Twelve Tables. Thus it belonged to his office to establish laws according to equity and the present condition of the city. That power was moderated, both because its end was equity and because it was annual; and if he had pronounced judgment inequitably, not only was his rejection from the consulship certain, but an accuser also threatened him. Nevertheless, it was later judged proper to make the praetors’ edicts perpetual, as was provided by the Cornelian law.
The determinations of princes are those occasions when the emperor has either given a rescript, rendered judgment, or prescribed something by edict. That power was given to Caesar through the Royal Law, so that the whole ordering of laws, just as the state itself, came to one man.
Finally, the opinions of prudent men are the judgments of jurists who formerly gave opinions concerning right with public authority. A judge was not permitted to depart from their consensus. The Institutes, book 1, title 2, § 8, speaks thus about them: “The opinions of prudent men are the judgments and opinions of those to whom it was permitted to give opinions concerning right. For in antiquity it was established that there should be persons who publicly interpreted laws, to whom Caesar gave the right of giving opinions and who were called jurisconsults. The judgments and opinions of all of them possessed such authority that a judge was not permitted to depart from their opinion, as has been established. Unwritten law is that which usage has approved. For customs of long standing, confirmed by the consent of those who use them, imitate law. And it seems not inelegant that civil law has been distributed into two species, for its origin appears to have flowed from the institutions of two cities, namely Athens and Lacedaemon. In these cities it was customary to proceed in such a way that the Lacedaemonians committed to memory those things which they observed as laws, whereas the Athenians preserved those things which they had embraced in written laws. But natural rights, which are for the most part observed among all nations, remain always firm and immutable, having been established by a certain divine providence. Those things, however, which each city establishes for itself are often accustomed to be changed, either by the tacit consent of the people or by another law subsequently enacted. Moreover, all the right which we use pertains either to persons, to things, or to actions; and let us first consider persons, for it is a small thing to know right if the persons for whose sake it was established are unknown.”
In this manner, therefore, the emperor himself defines and divides right—but written right, as he says. For customs, about which I shall speak in their proper place, pertain elsewhere. For Charles Sigonius, in book 1, chapter 5 of On the Ancient Law of the Romans, makes law twofold, namely, one part consisting in writing and the other in custom. And indeed the laws of some cities were not written, as Justinian testifies. Custom and the institutions of the ancestors brought unwritten right into the state, and by their equity the austerity of the law was often tempered.
§ 7. Certainly, among an uncultivated people there was no law at the beginning. A book of Roman law was compiled in the times of Tarquinius Superbus, concerning which Pomponius says: “At the beginning of our city, the people began at first to conduct affairs without fixed law and without fixed right, and all things were governed by the hand of the kings. Later, after the city had increased to some extent, Romulus himself is said to have divided the people into thirty parts, which he called curiae, because at that time he administered the care of the state through the judgments of those parts. Thus he himself proposed certain curiate laws to the people, and the succeeding kings also proposed them. All these laws remain compiled in the book of Sextus Papirius, who lived in those times in which Superbus, the son of Demaratus the Corinthian, was among the foremost men. That book, as we have said, is called the Papirian civil law—not because Papirius added anything of his own there, but because he brought together into one collection laws enacted without order.”
But they lived more by royal will than by right. Therefore, after the tyrants had been expelled and liberty had been afflicted by the domination of the patricians, thought was given to laws. From this arose the Twelve Tables, which contained a threefold right, or three kinds of laws. Ausonius, in the Riddle of the Number Three:
The threefold law of the Tables, which four times three sanctioned: Sacred, private, and whatever was common to the people.
Actions, procedures, and formulas were appended to the laws. At first these were employed to shorten lawsuits, lest each person conduct cases according to his own discretion; but afterward Gnaeus Flavius published the formulas, whence came the Flavian law. Aelius added other actions, which the uncultivated multitude called the Aelian law. For when contention occurs in the forum, the brawler generally gains more authority than the jurist. And these observations suffice concerning the descriptions and divisions of right and laws, about which novices in political philosophy are customarily instructed at very great length.