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A term derived from the Roman civil law , defined in the "Institutes" of Justinian as a "legal bond which by a legal necessity binds us to do something according to the laws of our State" (III, 13). It was a relation by which two persons were bound together ( obligati ) by a bond which the law recognized and enforced. Originally both parties were considered to be under the obligation to each other; subsequently the term was restricted to one of the parties, who was said to be under an obligation to do something in favour of another, and consequently that other had a correlative right to enforce the fulfilment of the obligation. The transference of the term from the sphere of law to that of ethics was easy and natural. In ethics it acquired a wider meaning and was used as a synonym for duty. It thus became the centre of some of the fundamental problems of ethics. The question of the source of moral obligation is perhaps the chief of these problems, and it is certainly not one of the easiest or least important. We all acknowledge that we are in general under an obligation not to commit murder, but when we ask for the ground of the obligation, we get almost as many different answers as there are systems of ethics.

The prevailing Catholic doctrine may be explained in the following terms. By moral obligation we understand some sort of necessity, imposed on the will, of doing what is good and avoiding what is evil. The necessity, of which there is question here, is not the physical coercion exercised on man by an external and stronger physical force. If two strong men seize me by the arms and drag me whither I would not go, I act under necessity or compulsion, but this is not the necessity of moral obligation. The will, which is the seat of moral obligation, is incapable of being physically coerced in that manner. It cannot be forced to will what it does not will. It is indeed possible to conceive that the will is necessitated to action by the antecedent conditions. The doctrine of those who deny free will is easily intelligible although we deny that it is true. The will is indeed necessitated by its own nature to tend towards the good in general; we cannot wish for what is evil unless it presents itself to us under the appearance of good. We also necessarily wish for happiness, and if we found ourselves in presence of some object which fully satisfied all our desires and contained in itself nothing to repel us, we should be necessitated to love it. But in this life there is no such object which can fully satisfy all our desires and thus make us completely happy. Health, friends, fame, wealth, pleasures, singly or all combined, are incapable of filling the void in our hearts. Though in their measure desirable, all earthly goods are limited, and man's capacity for good is unlimited. All earthly goods are defective; we recognize their defects and the evil which the pursuit or possession of them entails. Considered with their defects, they repel as well as attract us; our wills therefore are not necessitated by them. In the presence of any earthly good our wills are free, at least after the first involuntary tendency to what attracts them; they are not necessitated to full and deliberate action.

The necessity, then, which constitutes the essence of moral obligation must be of the kind which an end that must be attained lays upon us of adopting the necessary means towards obtaining that end. If I am bound to cross the ocean and I am unable to fly, I must go on board ship. That is the only means at my disposal for attaining the end which I am bound to obtain. Moral obligation is a necessity of this kind. It is the necessity that I am under, of employing the necessary means towards the obtaining of an end which is also necessary. The necessity, then, which moral obligation lays upon us is the necessity, not of the determinism of nature, nor of the physical coercion of an external and stronger force, but it is of the same general character as the necessity that we are under of employing the necessary means in order to attain an end which must be obtained. There is, however, a special quality in the necessity of moral obligation which is peculiar to itself. We all appreciate this when we say that children are "obliged" to obey their parents, that they "ought" to obey them, that it is their " duty " to do so. We do not simply mean by those assertions that obedience to parents is a necessary means towards their own education, and for securing the peace, harmony, and affection, which should reign in the home. We do not simply mean that the happiness of parents and children depends upon such obedience. Although society at large is much concerned that children should be trained in respect and deference towards lawful authority, yet even the demands of society do not explain what we mean when we affirm that children are obliged to obey their parents. There is a peremptoriness, a sacredness, a universality about the obligation of duty, which can only be explained by calling to mind what man is, what is his origin, and what is his destiny. Man is a creature, made by God his Creator, with Whom he is destined to live for all eternity. That is the end of man's life and of his every action, imposed on him by his Maker, who in making man ordered every fibre of his nature to the end for which he was made. That doctrine explains the peremptoriness, the sacredness, the universality of moral obligation, made known to us, as it is, by the dictates of conscience. The doctrine has seldom been put in clearer or more beautiful language than by Cardinal Newman in his Letter to the Duke of Norfolk (p. 55):

The Supreme Being is of a certain character, which, expressed in human language, we call ethical. He has the attributes of justice, truth, wisdom, sanctity. benevolence and mercy, as eternal characteristics in His Nature, the very Law of His being, identical with Himself; and next, when He became Creator, He implanted this Law, which is Himself, in the intelligence of all His rational creatures. The divine Law then is the rule of ethical truth, the standard of right and wrong, a sovereign, irreversible, absolute authority in the presence of men and Angels. "The eternal law," says St. Augustine, "is the Divine Reason or Will of God, commanding the observance, forbidding the disturbance, of the natural order of things." "The natural law," says St. Thomas, "is an impression of the Divine Light in us, a participation of the eternal law in the rational creature." This law, as apprehended in the minds of individual men, is called "conscience"; and though it may suffer refraction in passing into the intellectual medium of each, it is not thereby so affected as to lose its character of being the Divine Law, but still has as such, the prerogative of commanding obedience. "The Divine Law," says Cardinal Gousset, "is the supreme rule of actions; our thoughts, desires, words, acts, all that man is, is subject to the domain of the law of God ; and this law is the rule of our conduct by means of our conscience." Hence it is never lawful to go against our conscience ; as the Fourth Lateran Council says, "Quidquid fit contra conscientiam, aedificat ad gehennam." . . . The rule and measure of duty is not utility, nor expedience, nor the happiness of the greatest number, nor State convenience, nor fitness, order, and the pulchrum. Conscience is not a long-sighted selfishness, nor a desire to be consistent with oneself; but it is a messenger from Him who both in nature and in grace, speaks to us behind a veil, and teaches and rules us by His representatives. Conscience is the aborigrinal Vicar of Christ, a prophet in its informations, a monarch in its peremptoriness, a priest in its blessings and anathemas, and even though the eternal priesthood throughout the Church could cease to be, in it the sacerdotal principle would remain and would have a sway.

An injustice would be done to the foregoing doctrine if it were classed with Mysticism. innate ideas. and Intuitionism. On the contrary, it is in the strictest sense rational. It asserts that we can know God our Creator and Lord, that we can know ourselves and the bonds that bind us to God and to our fellow men. We can know the actions which it is right and becoming that such a being as man should perform. We can and do know that God, Whom as our Creator and Lord we are bound to obey, commands us to do what is right and forbids us to do what is wrong. That is the eternal law, the Divine reason or the Divine will, which is the source of all moral obligation. Moral precepts are the commands of God, but they are also the behests of right reason, inasmuch as they are merely the rules of right conduct by which a being such as man is should be guided.

An objection is sometimes urged against the method of analysing moral obligation which we have followed. It is said that moral obligation cannot be explained as a moral necessity of adopting the necessary means to the end of moral action, for it may be asked what is the moral obligation of the end itself. The Utilitarians, for example, maintained that the end of human action should be the greatest happiness of the greatest number. But a man may well ask, why he should be bound to direct his actions towards securing the greatest happiness of the greatest number. It is plain what answer should be given to such a question on the principles laid down above. God is our Creator and Lord, and as such and because He is good, He has every right to our obedience and service. We need not go beyond the preceptive will of God in our analysis ; it is obligatory upon us from the very nature of God and our relation to Him. The rules of morality are then moral laws imposing on us an obligation derived from the will of God, our Creator. That obligation is the moral necessity that we are under of conforming our actions to the demands of our rational nature and to the end for which we exist. If we do what is not conformable to our rational nature and to our end, we violate the moral law and do wrong. The effect on ourselves of such an action is twofold according to Catholic theology. A bad action does not merely subject us to a penalty assigned to wrongdoing, the sanction of the moral law. Besides this reatus poenoe , there is also the reatus culpa in every moral transgression. The sinner has committed an offence against God, something which displeases Him, and which puts an end to the friendship which should exist between the Creator and creature. This state of enmity is accompanied, in the supernatural order to which we have been raised, by the privation of God's grace, and of the rights and privileges annexed to it. This is by far the most important of the effects produced on the soul by sin, the liability to punishment is merely a secondary consequence of it. This shows how far from the truth we should be if we attempted to explain moral obligations by mere liability to punishment which wrongdoing entails in this world or in the next.

The sense of moral obligation is an attribute of man's rational nature, and so we find it wherever we find man. However, in the early history of ethical speculation the notion is not prominent. Before philosophers began to inquire into the meaning and origin of moral obligation, they busied themselves about what is the good, and what the end of human activity. This was the question which occupied the philosophers of ancient Greece. What is the highest good for man ? In what does man's happiness consist? Is it pleasure, or virtue practised for its own sake or for the gratification and self-esteem that it brings to the virtuous man ? With the exception of the Stoics, the Greek philosophers did not much discuss the question of duty and moral obligation. They thought that, of course, when a man knew where his highest good lay, he could not but pursue it. Vice was really ignorance, and all that was necessary to subdue it was a training in philosophy. But the first principle of the Stoics was: "life according to nature ". That was the "becoming", the "proper" thing, whether it brought pleasure or pain, which the Stoic philosopher indeed reckoned of no importance and affected to despise. This philosophy appealed powerfully to the native sternness of the Roman character, and it was considerably influenced and developed by the ideas of Roman jurisprudence. Thus the treatise of Panaetius, a Stoic of the second century before Christ, "On the Things That Are Becoming", was paraphrased by Cicero in the next century, and became his well-known treatise "On Duties." Cicero remarks, and the remark is significant, that Panaetius had not given a definition of what duty is. According to Cicero it has reference to the end of good actions, and is expressed in precepts to which the conduct of life can be conformed in all its particulars (De officiis, I, iii). The working out of the doctrine concerning the law of nature is due to a large extent to the Roman lawyers, and Costa Rosetti, a recent Austrian writer on ethics, could find no words more suited to sum up the common Catholic teaching on the point than a passage from Cicero's "De republica" (III, xxii). We cannot do better than give a translation of the passage here, as it will show clearly how fully the doctrine of a law of nature imposing a moral obligation on man had been developed before it was adopted by the Fathers (Lactantius, Divine Institutes , VI, 8 ):

Right reason is a true law, agreeing with nature, infused into all men, unchanging,eternal, which summons to duty by its commands, deters from wrong by forbidding it, and which nevertheless neither commands and forbids the good in vain, nor prevails with the bad by commanding and forbidding them. It is not permitted to abrogate this law, nor is it allowed to derogate from it in anything, nor is it possible to abrogate it wholly. We can neither be released from this law by popular vote, nor should another be sought for to gloss and interpret it. It is not one thing at Rome, another at Athens ; one thing now, and another afterwards; but one. eternal and immutable law will govern all men for ever, and there will be one, the common master and ruler of all, God. He it was that proposed and carried this law, and whoever does not yield obedience to it will revolt against himself and byoffering an affront to the nature ofman he will thereby suffer the greatest penalties, even if he avoids other supposedsanctions.

The Stoic indeed understood this doctrine in a pantheistic sense. His god was the universal reason of the world, of which a particle was bestowed on man at his birth. It only needed the Christian doctrine of a personal God, the Creator and Lord of all things, Who in many ways manifests His law to man, but more especially through and in the voice of conscience, to turn it into the Catholic doctrine of moral obligation which has been analysed above. In the teaching of Christ, right conduct is summed up in the observance of the commandments. Those commandments constitute the law of God, which He came not to destroy but to fulfil. He required their observance under the most terrible sanctions. St. Paul, of course, only preached the doctrine of his Master. The legalism which he rejected was the ceremonial and the merely outward observance of the Pharisees, not the internal and the external observance of the moral law. Although the Gentile had not the moral law written on tablets of stone, yet he had it written on the fleshy tablets of his heart, and his conscience bore witness to it, as did that of the Jew ( Romans 2:14 ). This is the doctrine still taught in the Catholic Church. It derives straight from Christ and His Apostles, though it is often expressed in the language of Stoicism, interpreted according to the exigences of Christian doctrine. Since the Reformation it has been the fashion with many to reject it as legalism in favour of what is called Christian liberty. Christian liberty, however, interpreted by private judgment, developed into various systems of so-called independent morality.

Thomas Hobbes (1588-1679) is justly regarded as one of the chief pioneers of modern thought. According to Hobbes, man in the state of nature seeks nothing but his own selfish pleasure, but such individualism naturally leads to an internecine war in which every man's hand is against his neighbour. In pure self-interest and for self-preservation men entered into a compact by which they agreed to surrender part of their natural freedom to an absolute ruler in order to preserve the rest. The State determines what is just and unjust, right and wrong; and the strong arm of the law provides the ultimate sanction for right conduct. The same fundamental principles form the groundwork of the empirical philosophy of Locke and a long train of followers down to the present day. Some of these followers indeed denied that all the motives that influence man's conduct are selfish; they insist on the existence of symphatetic and social feelings in men, but whether selfish or social, all are rooted in a sensist philosophy. The lineal descent of these views may be traced from Hobbes and Locke, through Hume, Paley, Bentham, the two Mills, and Bain, to H. Spencer and the Evolutionists of our own day. This sensist philosophy, of course, has had its opponents. Cudworth and the Cambridge Platonists strove to defend the essential and eternal distinction of good and evil by reviving Platonism. Butler insisted on the claims of conscience, while the Scotch school, Price, Reid, and Dugald Stewart, postulated a moral sense analogous to the sense of beauty, which infallibly indicates the right course of conduct. In Germany Kant formulated his ethical system to counteract the scepticism of Hume. Moral obligation, according to him, is derived from the categorical imperative of the autonomous reason. Kant's philosophy, through Fichte and Schelling, gave birth to the pantheism of Hegel. A small but influential school of English Hegelians, represented by such men as T. H. Green, Bradley, Wallace, Bosanquet, and others, regard conscience as the voice of man's true self, and man's true self as ideally one with God. English philosophic thought is thus divided into the schools of Materialism and Pantheism, much as Epicureanism and Stoicism divided the ancient world. Pragmatism, a product of American thought, may without injustice be compared to the scepticism of the Athenian Academy. Each and all of these systems contain grave errors about the nature of man and about his position in the world, and so it is no wonder that they fail to account for moral obligation. (See DETERMINISM; DUALISM; DUTY; ETHICS; FATALISM; FREE WILL; HEDONISM; KANT, PHILOSOPHY OF; LAW; PANTHEISM; POSITIVISM.)


The office of a judge, inasmuch as he is appointed by public authority to administer justice according to the laws demands in the first place competent knowledge of the laws which are to be administered. Not less important in a judge is a lofty sense of justice and an upright character which cannot be deflected from the path of duty by either fear or favour. The judge, too, must employ at least ordinary diligence in the conduct of the cases that come before him, so that as far as possible a just sentence may be arrived at. He must not transgress the limits of his authority, and he must observe the rules of procedure laid down for his guidance. These obligations of a judge follow from the nature of his office, and he binds himself implicitly to fulfil them when he accepts that office. Judges also usually take an oath by which they expressly bind themselves to administer justice uprightly, without fear or favour. Selling justice for bribes is rightly regarded as a heinous offence in a judge, and besides being liable to severe punishment, it involves the obligation of making restitution, as there is no just title to retain the price of justice. Natural equity requires that all should be presumed to be innocent who have not been proved to be guilty of crime, and so a judge must give those who are accused the benefit of the doubt, when the crime imputed to them cannot be clearly proved. In civil actions he is bound to give sentence according to the merits of the case, and so in default of certainty of right, he must decide in favour of the party who has the better claim. What has been said of judges is applicable in due measure to magistrates, referees, arbitrators, and jurymen, all of whom are invested with some of the functions of a judge.

Advocates and lawyers are persons skilled in the law who for payment undertake the legal business of clients. They are obliged to have the knowledge and skill which are required for the due discharge of their office, and which they implicitly profess to have when they offer their services to the public. They must also employ at least ordinary diligence and care in the conduct of the business entrusted to them. They must keep faith with their clients and use only just means to obtain the objects which they desire. As they act for and in the name of their clients, they must not undertake a cause which is clearly unjust, otherwise they will be guilty of co-operating in injustice, and will be bound to make restitution for all the unjust damage which they cause to others. However, previous certainty of the justice of a cause is not necessary in order that a lawyer may rightly undertake it; it will be sufficient if the justice of the cause to be undertaken is at least probable, for then it may be hoped that the truth will be made clear in the course of the trial. As soon as an attorney is satisfied that his client has no case, he should inform him of the fact, and should not proceed further with the case. An attorney may always undertake the defence of a criminal, whether he be guilty or not, for even if his defence of a real culprit is successful, no great harm will usually be done by a guilty man escaping the punishment which he deserves. To justify a criminal accusation of another there must be morally certain evidence of his guilt, as otherwise there will be danger of doing serious and unjust harm to the reputation of one's neighbour.

From the Decree of the Holy Office, 19 December, 1860, in answer to the Bishop of Southwark, it is clear that in England an attorney may undertake a case where there is question of judicial separation between husband and wife. Even in an action for divorce in a civil court he may defend the action against the plaintiff. If the marriage has already been pronounced null and void by competent ecclesiastical authority a Catholic attorney may impugn its validity in the civil courts. Moreover, for just reason, as, for example, to obtain a variation in the marriage settlement, or to prevent the necessity of having to maintain a bastard child, a Catholic lawyer may petition for a divorce in the civil court, not with the intention of enabling his client to marry again while his spouse is still living but with a view to obtaining the civil effects of divorce in the civil tribunal. This opinion at any rate is defended as probable by many good theologians. The reason is because marriage is neither contracted nor dissolved before the civil authority ; in the formalities prescribed for marriage by civil law there is only question of the civil authority taking cognizance of who are married, and of the civil effects which now therefrom.

In canon law excommunicated and infamous persons, accomplices, and others are debarred from prosecuting criminals, but as a general rule any one who has full use of his senses may prosecute according to American and English law. Nobody should undertake a prosecution when greater evil than good would follow from it, or when there is not moral certainty as to the guilt of the accused. However, it may be done for the sake of the public good, and there may be an obligation to do it, as when one's office compels one to undertake the task, or the defence of the innocent or the public good requires it, or a precept of obedience commands it. Thus by ecclesiastical law heretics and priests guilty of solicitation in the sacred tribunal are to be denounced to the ordinary.

The defendant in a criminal trial is not himself subjected to examination, according to English law, unless he offers himself voluntarily to give evidence, and then he may be examined like a witness. In canon law the accused is examined. and the question arises whether he is bound to tell the truth against himself. He is bound to tell the truth if he is interrogated according to law ; canon law prescribes that when there is semiplena probatio of the crime and this is made clear to the defendant he should be interrogated.

The defendant may in self-defence make known the secret crime of a witness against him, if it really conduces to his defence; but, of course, he may never impute false crimes to anybody. A criminal may not defend himself against lawful arrest, for that would be to resist lawful authority, but he is not compelled to deliver himself up to justice, and it is not a sin to escape from justice if he can do so without violence. The law prescribes that he shall be kept in durance, not that he shall voluntarily remain in custody. A criminal lawfully condemned to death is not obliged to save his life by escape or other means if he can do so; he should submit to the execution of the sentence passed upon him, and may do so meritoriously.

Charity or obedience may impose an obligation to give evidence in a court of justice. If serious harm can be prevented by offering one's self as a witness, there will as a rule be an obligation to do so, and obedience imposes the obligation when one is summoned by lawful authority. A witness is bound by his oath and by the obedience due to lawful authority to tell the truth in answer to the questions lawfully put to him. He is not bound to incriminate himself, nor, of course, may the seal of confession ever be broken.

The canon law laid it down that the testimony of two witnesses of unsuspected character was necessary and sufficient evidence of any fact alleged in a court of justice. The testimony of a solitary witness was not usually sufficient or admissible evidence of a crime, and in keeping with this the theologians decided that a solitary witness should not declare what he knew of a crime, inasmuch as he was not lawfully interrogated. English law, however, with most modern systems, admits the testimony of one witness, if credible, as sufficient evidence of a fact, and so as a rule there will be an obligation on such a one of answering according to his knowledge when questioned lawfully in a court of justice.

A doctor who holds himself out as ready to undertake the care of the sick must have competent knowledge of his profession and must exercise his office at least with ordinary care and diligence; otherwise he will sin against justice and charity in exposing himself to the risk of seriously injuring his neighbour. Unless he is bound. by some special agreement he is not ordinarily obliged to undertake any particular case for there are usually others who are willing and able to give the necessary assistance to the sick. Even in time of pestilence he will not commit sin if he leave the neighbourhood, unless he is bound to remain by some special contract.

He should not make exorbitant charges for his services, nor multiply visits uselessly and thus increase his fees, nor call in other doctors without necessity. On the other hand, even at serious inconvenience, he should visit a patient whose case he has undertaken when called as far as is reasonable, and he should be ready to call in other doctors for consultation when necessary or when he is asked to do so. He is sometimes bound by the general law of charity to give his assistance gratis to the poor.

He may not neglect safer remedies in order to try those which are less safe, but there is nothing to prevent him from prescribing what will probably do good if it is certain that it will not do harm. In a desperate case, with the consent of the sick person and of his relations, he may make use of what will probably do good though it may also probably do harm, provided that there is nothing better to be done in the circumstances. It is altogether wrong to make experiments with doubtful remedies or operations on living human beings ; fiat experimentum tn corpore vili.

When the patient is in danger of death, the doctor is bound out of charity to warn him or those who attend on him, that he may make all necessary preparations for death. (See ABORTION; ANAESTHESIA; CRANIOTOMY; HYPNOTISM.)

Teachers hold the place of parents with regard to those committed to their charge for the purpose of instruction. They are bound in justice to exercise due care and diligence in the discharge of their office. They must have the knowledge and skill which that office demands.

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