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Concept of law

A. By law in the widest sense is understood that exact guide, rule, or authoritative standard by which a being is moved to action or held back from it. In this sense we speak of law even in reference to creatures that are incapable of thinking or willing and to inanimate matter. The Book of Proverbs (ch. viii) says of Eternal Wisdom that it was present when God prepared the heavens and when with a certain law and compass He enclosed the depths, when He encompassed the sea with its bounds and set a law to the waters that they should not pass their limits. Job (xxviii, 25 sqq.) lauds the wisdom of God Who made a weight for the winds and weighed the water by measure, Who gave a law for the rain and a way for the sounding storms.

Daily experience teaches that all things are driven by their own nature to assume a determinate, constant attitude. Investigators of the natural sciences hold it to be an established truth that all nature is ruled by universal and constant laws and that the object of the natural sciences is to search out these laws and to make plain their reciprocal relations in all directions. All bodies are subject, for example, to the law of inertia, i.e. they persist in the condition of rest or motion in which they may be until an external cause changes this condition. Kepler discovered the laws according to which the planets move in elliptical orbits around the sun, Newton the law of gravitation by which all bodies attract in direct proportion to their mass and inversely as to the square of the distance between them. The laws which govern light, heat, and electricity are known today. Chemistry, biology, and physiology have also their laws. The scientific formulae in which scholars express these laws are only laws in so far as they state what processes actually take place in the objects under consideration, for law implies a practical rule according to which things act. These scientific formulae exert of themselves no influence on things; they simply state the condition in which these things are. The laws of nature are nothing but the forces and tendencies to a determinate, constant method of activity implanted by the Creator in the nature of things, or the unvarying, homogeneous activity itself which is the effect of that tendency. The word law is used in this latter sense when it is asserted that a natural law has been changed or suspended by a miracle. For the miracle does not change the nature of things or their constant tendency; the Divine power simply prevents the things from producing their natural effect, or uses them as means to attaining an effect surpassing their natural powers. The natural tendency to a determinate manner of activity on the part of creatures that have neither the power to think nor to will can be called law for a twofold reason: first, because it forms the decisive reason and the controlling guide for the activities of such creatures, and consequently as regards irrational creatures fulfills the task which devolves upon law in the strict sense as regards rational beings; and further, because it is the expression and the effect of a rational lawgiving will. Law is a principle of regulation and must, like every regulation, be traced back to a thinking and willing being. This thinking and willing being is the Creator and Regulator of all things, God Himself. It may be said that the natural forces and tendencies placed in the nature of creatures, are themselves the law, the permanent expression of the will of the Eternal Observer Who influences creatures and guides them to their appointed ends, not by merely external influences but by their innate inclinations and impulses.

B. In a stricter and more exact sense law is spoken of only in reference to free beings endowed with reason. But even in this sense the expression law is used sometimes with a wider, sometimes with a more restricted meaning. By law are at times understood all authoritative standards of the action of free, rational beings. In this sense the rules of the arts, poetry, grammar, and even the demands of fashion or etiquette are called laws. This is, however, an inexact and exaggerated mode of expression. In the proper and strict sense laws are the moral norms of action, binding in conscience, set up for a public, self-governing community. This is probably the original meaning of the word law, whence it was gradually transformed to the other kinds of laws (natural laws laws of art). Law can in this sense be defined with St. Thomas Aquinas (Summa Theologica I-II:90:4) as: A regulation in accordance with reason promulgated by the head of a community for the sake of the common welfare.

Law is first a regulation, i.e. a practical principle, which aims at ordering the actions of the members of the community. To obtain in any community a unified and systematized co-operation of all there must be an authority that has the right to issue binding rules as to the manner in which the members of the community are to act. The law is such a binding rule and draws its constraining or obligatory force from the will of the superior. Both because the superior wills and so far as he wills, is law binding. Not every regulation of the superior, however, is binding, but only those in accordance with reason. Law is the criterion of reasonable action and must, therefore, itself be reasonable. A law not in accordance with reason is a contradiction. That the Divine laws must of necessity be reasonable and just is self-evident, for the will of God is essentially holy and just and can only command what is in harmony with the Divine wisdom, justice, and holiness. Human laws however, must be subordinate to the Divine law, or at least, must not contradict it, for human authority is only a participation in the supreme Divine power of government, and it is impossible that God could give human beings the right to issue laws that are unreasonable and in contravention of His will. Further, law must be advantageous to the common welfare. This is a universally acknowledged principle. That the Divine laws are advantageous to the common welfare needs no proof. The glory of the Creator is, truly, the final goal of the Divine laws but God desires to attain this glory by the happiness of mankind. Human laws must also be useful to the common welfare. For laws are imposed upon the community as such, in order to guide it to its goal: this goal, however, is the common welfare. Further, laws are to regulate the members of the community. This can only come about by all striving to attain a common goal. But this goal can be no other than the common welfare. Consequently all laws must in some way serve the common welfare. A law plainly useless or a fortiori injurious to the community is no true law. It could have in view only the benefit of private individuals and would consequently subordinate the common welfare to the welfare of individuals, the higher to the lower.

Law therefore is distinguished from a command or precept by this essential application to the common welfare. Every law is a form of command but not every command is a law. Every binding rule which a superior or master gives to his subordinates is a command; the command, however, is only a law when it is imposed upon the community for the attainment of the common welfare. In addition, the command can be given for an individual person or case. But law is a permanent, authoritative standard for the community, and it remains in force until it is annulled or set aside. Another condition of law is that it should proceed from the representative of the highest public authority, be this a single person, several persons, or finally the totality of all the members of the community, as in a democracy. For law is, as already said, a binding rule which regulates the community for the attainment of the common welfare. This regulation pertains either to the whole community itself or to those persons in the highest position upon whom devolves the guidance of the whole community. No order or unity would be possible if private individuals had the liberty to impose binding rules on others in regard to the common welfare. This right must be reserved to the supreme head of the community. The fact that law is an emanation of the highest authority, or is issued by the presiding officer of the community by virtue of his authority, is what distinguishes it from mere counsels, requests, or admonitions, which presuppose no power of jurisdiction and can, moreover, be addressed by private persons to others and even to superiors. Laws, finally, must be promulgated, i.e. made known to all. Law in the strict sense is imposed upon rational, free beings as a controlling guide for their actions; but it can be such only when it has been proclaimed to those subject to it. From this arises the general axiom: Lex non promulgata non obligat--a law which has not been promulgated is not binding. But it is not absolutely necessary to promulgation that the law be made known to every individual; it suffices if the law be proclaimed to the community as such, so that it can come to the notice of all members of the community. Besides, all laws do not require the same kind of promulgation. At present, laws are considered sufficiently promulgated when they are published in official journals (State or imperial gazettes, law records, etc.)

In addition to the moral law as treated above, it is customary to speak of moral laws in a wider sense. Thus it is said it is a moral law that no one is willingly deceived, that no one lies without a reason, that every one strives to learn the truth. But it is only in an unreal and figurative sense that these laws are called moral. They are in reality only the natural laws of the human will. For although the will is free, it remains subject to certain inborn tendencies and laws within which bounds alone it acts freely, and these laws are called moral only because they bear on the activities of a free will. Therefore they are not expressed by an imperative "must". They merely state that by reason of inborn tendencies, men are accustomed to act in a given way, and that such laws are observed even by those who have no knowledge of them.

To understand still better the significance of moral law in the strict sense, henceforth the sole sense intended in this article, two conditions of such law should be considered. It exists first in the intellect and will of the lawgiver. Before the lawgiver issues the law he must apprehend it in his mind as a practical principle, and at the same time perceive that it is a reasonable standard of action for his subjects and one advantageous to the common welfare. He must then have the will to make the observance of this principle obligatory on those under him. Finally, he must make known or intimate to those under him this principle or authoritative standard as the expression of his will. Strictly construed, legislation in the active sense consists in this last act, the command of the superior to the inferiors. This command is an act of the reason, but it necessarily presupposes the aforesaid act of the will and receives from the latter its entire obligatory force. The law, however, does not attain this obligatory force until the moment it is made known or proclaimed to the community. And this brings us to the point that the law can be considered objectively, as it exists apart from the lawgiver. At this stage law exists either in the mind of the subjects or in any permanent token which preserves the memory of it, e.g. as found in a collection of laws. Such outward tokens, however, are not absolutely necessary to law. God has written the natural moral law, at least in its most general outlines, in the hearts of all men, and it is obligatory without any external token. Further, an external, permanent token is not absolutely necessary for human laws. It suffices if the law is made known to the subjects, and such knowledge can be attained by oral tradition.

Obligation imposed by law

Law (in the strict sense) and command are preeminently distinguished from other authoritative standards of action, inasmuch as they imply obligation. Law is a bond imposed upon the subjects by which their will is bound or in some way brought under compulsion in regard to the performance or the omission of definite actions. Aristotle, therefore, said long ago that law has a compelling force. And St. Paul (Romans 13:1 sqq.) teaches that we are bound to obey the ordinances of the authorities not only through fear but also for conscience' sake. In what then does this obligation which law imposes upon us consist? Modern ethical systems which seek to construct a morality independent of God and religion, are here confronted by an inexplicable riddle. The utmost pains have been taken to construct a true obligation without regard to God. According to Kant our reason itself is the final source of obligation, it obliges us of itself, it is nomothetic and autonomous, and the absolute form in which it commands us is the categorical imperative. We are obliged to fulfil the law only on account of itself or because it is the law of our reason; to do something because another has commanded us is not moral, even should this other be God. This view is entirely untenable. We do not owe obedience to the laws of Church and State because we bind ourselves thereto, but because their superior authority obliges us. The child owes obedience to its parents not because it engages so to do but because the authority of the parents obliges it. Whoever asserts that man can bind only himself, strikes at the root of all authority and asserts the principle of anarchism. Authority is the right to issue to others binding, obligatory regulations. Whoever maintains that none can put more than himself under obligation denies, thereby, all authority. What is said of human authority is equally valid of the Divine authority. We owe adoration, obedience, and love to God, not because we engage so to do, but because God obliges us by His commands. The assertion that to do something because God has commanded us is heteronomy (subjection to the law of another) and therefore not moral, implies in principle the destruction of all religion, which in its essence rests upon the subjection of the creature to his Creator.

The adherents of the Kantian autonomy can also be asked whether man binds himself of necessity or voluntarily? If voluntarily, then he can at any moment annul this obligation; consequently, in a practical sense, no obligation exists. If of necessity, the question arises whence comes this necessity to bind oneself unconditionally? To this question Kant has no answer to give. He refers us to an undemonstrable and incomprehensible necessity. He says: "All human reason is incapable of explaining how pure reason may be practical (imposing obligation)....Thus, it is true, we do not comprehend the practical, unconditioned necessity of the moral imperative, but we do, however, comprehend its incomprehensibility, which is all that can, in fairness, be demanded from a philosophy that seeks to reach the principles which mark the limit of human reason" ["Grundleg. zur Metaphys. der Sitten", ed. Hartenstein, IV (1838), 91-93]. Kant, who without hesitation sets aside all Christian mysteries, in this way imposes upon us in philosophy a mystery of his own invention. Kant's views contain a germ of truth, which, however, they distort until it can no longer be recognized. In order that a human law may be obligatory upon us we must have in ourselves from the beginning the conviction that we are to do good and avoid evil, that we are to obey rightful authority, etc. But the further question now arises, whence do we receive this conviction? From God, our Creator. Just as our whole being is an image of God, so also is our reason with its powers and inborn tendencies an image of the Divine Reason, and our cognitions which we involuntarily form in consequence of natural tendency are a participation in the Divine wisdom,--are, it may be said, a streaming in of the Divine light into the created reason. This is, indeed, not to be so understood as though we had innate ideas, but rather that the ability and inclination are inborn in us by virtue of which we spontaneously form universal concepts and principles, both in the theoretical and practical order, and easily discern that in these practical principles the will of the Supreme Director of all things manifests itself.

The Kantian philosophy has now but few adherents; most champions of independent ethics seek to explain the origin of duty by experience and development. Typical of writers on ethics of this school are the opinions of Herbert Spencer. This philosopher of evolution believed that he had discovered already in animals, principally in dogs, evidences of conscience, especially the beginnings of the consciousness of duty, the idea of obligation. This consciousness of duty is further developed in men by the accumulation of experiences and inheritance. Duty presents itself to us as a restraint of our actions. There are, however, several varieties of such restraints. The inner restraint is developed by induction, inasmuch as we discern by repeated experience that certain actions have useful, others injurious results. In this way we are attracted to the one, and frightened away from the other. Added to this is the external restraint, the fear of evil results or punishments which threaten us from without and are threefold in form. In the earliest stages of development man has to abstain from actions through fear of the anger of uncivilized associates (social sanction). At a higher stage man must avoid many actions, because such would be punished by a powerful and bold associate who has succeeded in making himself chief (state sanction). Finally, we have in addition the fear of the spirits of the dead, especially of the dead chiefs, who, it was believed, lingered near and still inflicted punishment upon many actions displeasing to them (religious sanction). The external restraint, i.e. the fear of punishment, created in mankind, as yet little developed, the concept of compulsion, of obligation in relation to certain actions. This concept originally arose only in regard to actions which were quickly followed by external punishments. Gradually, by association of ideas, it was also connected with other actions until then performed or avoided purely on account of their natural consequences. Through evolution, however, he goes on to say, the idea of compulsion, owing only to confusion or false generalization, tends to disappear and eventually is found only in rare cases. Spencer claimed to have found, even today, here and there men who regularly do good and avoid evil without any idea of compulsion. Most modern writers on ethics, who do not hold to a positive Christian point of view, adopt these Spencerian ideas, e.g. Laas, von Gizycki, Paulsen, Leslie, Fouillée, and many others. Spencer and his followers are nevertheless wrong, for their explanation of duty rests on entirely untenable premises. It presupposes that the animal has already a conscience, that man does not differ essentially from the animal, that he has gradually developed from a form of animal, that he possesses no essentially higher spiritual powers, etc. Moreover, their explanation of duty is meaningless. No one will assert of a man that he acts from duty if he abstains from certain actions through fear of police penalties, or the anger of his fellow-men. Besides, what is the meaning of an obligation that is only an accidental product of evolution, destined to disappear with the progress of the latter, and for disregarding which we are responsible to no superior?

In contrast with these modern and untenable hypotheses the Christian theistic conception of the world explained long since the origin and nature of duty in a fully satisfactory manner. From eternity there was present to the Spirit of God the plan of the government of the world which He had resolved to create. This plan of government is the eternal law (lex aeterna) according to which God guides all things towards their final goal: the glorifying of God and the eternal happiness of mankind. But the Creator does not move creatures, as men do, simply by external force, by pressure, or impact, and the like, but by tendencies and impulses which He has implanted in creatures and, what is more, in each one according to its individual nature. He guides irrational creatures by blind impulses, inclinations, or instincts. He cannot, however, guide in this way rational, free men, but only (as is suited to man's nature) by moral laws which in the act of creation He implanted in the human heart. As soon as man attains to the use of reason he forms, as already indicated, on account of innate predispositions and tendencies, the most general moral principles, e.g. that man is to do good and avoid evil, that man is to commit no injustice, etc. He also easily understands that these commands do not depend on his own volition but express the will of a higher power, which regulates and guides all things. By these commands (the natural moral law) man shares in a rational manner in the eternal law; they are the temporal expression of the eternal, Divine law. The natural moral law is also the foundation and root of the obligation of all positive laws. We recognize that we cannot violate the natural moral law, and the positive laws that are rooted in it, without acting in opposition to the will of God, rebelling against our Creator and highest Master, offending Him, turning away from our final end, and incurring the Divine judgment. Thus man feels himself to be always and everywhere bound, without losing his freedom in a physical sense, to the order appointed him by God. He can do evil but he ought not. If of his own will he violates God's law he brings guilt upon himself and deserves punishment in the eyes of the all-wise, all-holy, and absolutely just God. Obligation is this necessity, arising from this knowledge, for the human will to do good and avoid evil.

Classification of laws

A. The actual, direct effect of law is obligation. According to the varieties of duty imposed, law is classified as: commanding, prohibitive, permissive, and penal. Commanding laws (leges affirmativae) make the performance of an action, of something positive, obligatory; prohibitive laws (leges negativae), on the other hand, make obligatory an omission. The principle holds good for prohibitive laws at least if they are absolute, like the commands of the natural, moral law, ("Thou shalt not bear false witness", "Thou shalt not commit adultery", etc.) that they are always and for ever obligatory (leges negativae obligant semper et pro semper--negative laws bind always and forever), i.e. it is never permissible to perform the forbidden action. Commanding laws however, as the law that debts must be paid, always impose an obligation, it is true, but not for ever (leges affirmativae obligant semper, sed non pro semper--affirmative laws are binding always but not forever), that is, they continue always to be laws but they do not oblige one at every moment to the performance of the action commanded, but only at a certain time and under certain conditions. All laws which inflict penalties for violation of the law are called penal, whether they themselves directly define the manner and amount of penalty, or make it the duty of the judge to inflict according to his judgment a just punishment. Laws purely penal (leges mere poenales) are those which do not make an action absolutely obligatory, but simply impose penalty in case one is convicted of transgression. Thus they leave it, in a certain sense, to the choice of the subject whether he will abstain from the penal action, or whether, if the violation is proved against him, he will submit to the penalty. The objection cannot be raised that purely penal laws are not actual laws because they create no bounden duty, for they oblige the violator of the law to bear the punishment if the authorities apprehend and convict him. Whether a law is a purely penal law or not is not so easy to decide in an individual case. The decision depends on the will of the lawgiver and also upon the general opinion and custom of a community.

B. In treating of promulgation a distinction has to be made between natural moral law and positive law. The first is proclaimed to all men by the natural light of reason; positive laws are made known by special outward signs (word of mouth or writing). The natural moral law is a law inseparable from the nature of man; positive law, on the contrary, is not. In regard to the origin or source of law, a distinction is made between Divine and human laws according as they are issued directly by God Himself or by men in virtue of the power granted them by God. If man in issuing a law is simply the herald or messenger of God, the law is not human but Divine. Thus the laws which Moses received from God on Mount Sinai and proclaimed to the people of Israel were not human but Divine laws. A distinction is further made between the laws of Church and State according as they are issued by the authorities of the State or of the Church. Laws are divided as to origin into prescriptive and statute law. Prescriptive, or customary, law includes those laws which do not come into existence by direct decree of the lawgiving power, but by long continued custom of the community. Yet every custom does not give rise to a law or right. In order to become law a custom must be universal or must, at least, be followed freely and with the intention of raising it to law by a considerable part of the population. It must further be a custom of long standing. Finally, it must be useful to the common welfare, because this is an essential requisite of every law. Custom receives its binding, obligatory force from the tacit or legal approval of the lawgiver, for every true law binds those upon whom it is imposed. Only he can impose a binding obligation on a community on whom the supervision of it or the power of jurisdiction over it devolves. If the legislative power belongs to a people itself it can impose obligation upon itself as a whole, if it has not this power the obligation can only be formed with the consent of the lawgiver (see CUSTOM).

A classification of law, as limited to law administered in the courts, and familiar to Roman jurisprudence, is that of law in the strict sense and equity (jus strictum et jus aequum et bonum). Equity is often taken as synonymous with natural justice. In this sense we say that equity forbids that anyone be judged unheard. Frequently, however, we speak of equity only in reference to positive laws. A human lawgiver is never able to foresee all the individual cases to which his law will be applied. Consequently, a law though just in general, may, taken literally, lead in some unforeseen cases to results which agree neither with the intent of the lawgiver nor with natural justice, but rather contravene them. In such cases the law must be expounded not according to its wording but according to the intent of the lawgiver and the general principles of natural justice. A reasonable lawgiver could not desire this law to be followed literally in cases where this would entail a violation of the principles of natural justice. Law in the strict sense (jus strictum) is, therefore, positive law in its literal interpretation; equity, on the contrary, consists of the principles of natural justice so far as they are used to explain or correct a positive human law if this is not in harmony with the former. For this reason Aristotle (Ethica Nicomachea, V, x) calls equity the correction (epanorthoma) of statute or written law.


ST. THOMAS, Summa Theologica, I-II:90 sqq.; SUAREZ, De legibus et legislatore Deo, I; LAYMANN, Theologia moralis, I, tract. iv; BOUQUILLON, Theologia fundamentalis, no. 52 sqq.; TAPARELLI, Saggio teoretico di diritto naturale, I, s. 93 sqq.

About this page

APA citation. Cathrein, V. (1910). Law. In The Catholic Encyclopedia. New York: Robert Appleton Company.

MLA citation. Cathrein, Victor. "Law." The Catholic Encyclopedia. Vol. 9. New York: Robert Appleton Company, 1910. <>.

Transcription. This article was transcribed for New Advent by John F. Wagner Jr. In Gratitude to Msgr. J. Emmett Murphy.

Ecclesiastical approbation. Nihil Obstat. October 1, 1910. Remy Lafort, Censor. Imprimatur. +John M. Farley, Archbishop of New York.

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