The Law of War and Peace (1625)

by Hugo Grotius

On Good Faith Between Enemies

I.     Good faith is to be kept with enemies of every description.
1.   WE have said that, in respect to character and extent, what is permissible in war is considered either absolutely or with reference to a previous promise. The first part of the subject has now been finished; there remains the latter part, which concerns the good faith of enemies with one another.

Silius Italicus, a Roman consul, has well said:

      And best is he
      In military service, who from first to last
      Maintains good faith in wars.’

Xenophon in his oration On Agesilaus says: ‘So great and excellent a thing it is in all men, to be sure, but especially in the case of generals, to be and to be considered respecters of good faith.’

In his fourth speech On Leuctra Aristides says: ‘Those who are devoted to justice are especially revealed in the maintenance of peace and other public agreements.’ As Cicero, in fact, rightly declared in his On Ends, there is no one who does not approve and praise the quality of mind by which not only is no advantage sought but good’ faith is kept even to one’s disadvantage.

2.   Public faith, as Quintilian the father remarks, makes truces between armed foes and preserves the rights of states that have surrendered. In another passage the same author says: ‘Good faith is the strongest bond in human affairs; good faith is held in sacred esteem between enemies.’ Similarly Ambrose also: ‘Therefore it is clear that even in war good faith and justice ought to be preserved.’ Again, Augustine declares: ‘When faith is pledged, it must be kept even with an enemy against whom war is being waged.’

Those who are enemies do not in fact cease to be men. But all men who have attained to the use of reason are capable of possessing a right which has its origin in a promise. In Livy Camillus says that he had such an alliance with the Faliscans as nature had produced.

3.   From the association of reason and speech arises that binding force of a promise with which we are dealing. Because we have previously said that, in the opinion of many, lying to an enemy is either permissible, or free from wrong, it must not be thought that this view can be extended with like reason to pledged faith. For the obligation to speak the truth comes from a cause which was valid before the war, and may, perhaps, in some degree, be removed by the war; but a promise in itself confers a new right.

Aristotle recognized this distinction when, treating of veracity, he said: ‘We are not speaking of the person who is truthful in agreements and in those matters which have to do with justice and injustice. For these belong to a different virtue.’

4.   Of Philip of Macedon Pausanias says: ‘No one would rightly call him a good general who habitually disregarded oaths, broke treaties at every opportunity, and dishonored good faith more than all other men.’ Valerius Maximus has this characterization of Hannibal: ‘He declared war openly on the Roman people and Italy, but he waged war more bitterly against good faith herself, having delight in lies and deception as if in noble virtues. For this reason it has come to pass that, though otherwise he might have left the memory of a noble name, it is doubtful whether he ought to be considered an extraordinarily great or extraordinarily bad man.’ According to Homer the Trojans, troubled in conscience, thus accuse themselves:

      Now breaking sacred pledges
      And sworn good faith we fight; for us a crime is war.

II.     Refutation of the view that faith ought not to be kept with pirates and tyrants.
1.   Already in our previous discussion we have said that we ought not to accept the principles laid down by Cicero: ‘We should have no relations with tyrants, but rather the most absolute separation’; again, ‘A pirate is not classed in the number of regular enemies; with him there is no bond of good faith, and he does not respect a common oath.’ Seneca, too, said of a tyrant: ‘When the relationship of human rights was broken off, every bond, that bound him to me, was severed.’

From such a source arose the error of Michael of Ephesus, who in his commentary on the Nicomachean Ethics said that the violation of the wife of a tyrant did not constitute adultery.’ By a like error certain teachers of the Jews have made a similar statement about foreigners, whose marriages they considered void.

2.   Nevertheless Gnaeus Pompey finished the war with the Pirates in great part by means of treaties, promising to them their lives, and places in which they might live without plundering. Sometimes also tyrants have restored liberty after having agreed to immunity. In the third book of the Civil War Caesar writes that the Roman commanders made an agreement with the brigands and deserters who were in the Pyrenees mountains. Who will say that, if an agreement of any sort had been made, no obligation would have arisen from it?

Such agreements do not in fact share in that special community of legal obligations which the law of nations has introduced between enemies engaged in a formal and complete war. But because their authors are human beings they have a common share in the law of nature, as Porphyry has rightly maintained in his work On Abstaining from Animal Food. From this follows the consequence that the agreements must be kept. Thus Diodorus relates that Lucullus kept faith with Apollonius, a leader of runaway slaves, and Dio writes that Augustus, in order not to violate good faith, paid to the brigand Corocotta, who had delivered himself up, the reward placed on his head.

III.     Answer to the argument drawn from the fact that such persons deserve punishment, and the proof that this is not taken into account when they have been treated with.
1.   But let us see if a more plausible view can be presented than that expressed by Cicero.

The first consideration is that, as we have elsewhere explained, if we take into account the law of nature, atrocious criminals, who do not belong to any state, can be punished by any person whatsoever. But those who can be punished with the loss of life can also be deprived of their property and rights, as the same Cicero rightly said: ‘It is not contrary to nature to despoil, if you can, the person whom it is lawful to kill.’ Among the rights of such a person is the right arising from a promise. This right, therefore, can also be taken from him as a penalty.

I answer that the reasoning would hold good if one had not treated with the person in question as a malefactor; but if at any time we have treated with such a person as such’ we ought to consider that we have been treating in regard to the remission of the punishment belonging to his condition. The fact is, as we have said elsewhere, that that explanation must always be assumed which prevents an act from becoming without effect.

2.   According to Livy, Nabis made an apt reply when Quintius Flamini[n]us reproached him with being a tyrant: ‘As regards this title, I can reply that, whatever I am, I am the same that I was when you yourself, Titus Quintius, made the alliance with me.’ Later he says: ‘ I had already done these deeds, whatever they are, when you made the alliance with me.’ He adds: ‘If I had changed in anything, then I ought to offer an explanation of my lack of consistency; but since you are changing, you ought to offer an explanation of your inconstancy.’

In an address of Pericles to his fellow-citizens, according to Thucydides, there is a passage of similar purport: ‘ We shall permit the allied states to be free, if they were so at the time when the treaty was made.’

IV.     The fact that a promise has been extorted through fear presents no obstacle, if the fear was not felt as a personal fear by him who made the promise.
Next, the objection, which I mentioned elsewhere, may be brought forward, that the person who has caused a promise to be made through fear is bound to free the promisor, for the reason that he has caused the loss unjustly; that is, by means of an action opposed to the nature both of human liberty and of an act which ought to be free.

Though we admit that this is sometimes the case, yet it does not cover all promises made to brigands. For in order that the person, to whom a promise has been made, should be bound to free the promisor, it is necessary that he himself should have caused the promise by an unjust fear. If therefore any one has promised a ransom in order to release a friend from captivity, he will be bound to pay; for the fear did not affect the person who came of his own freewill to make the agreement.

V.     Or, if an oath has been given, the fact that a promise has been extorted through fear presents no obstacle, although in the case of a brigand such an oath is violated with impunity so far as men are concerned.
There is the further consideration that a person who has made a promise under the compulsion of an unjust fear can be obligated if the sanction of an oath has been added. For, as we have said elsewhere, a man is thereby bound not only to man but also to God, and in relation to Him fear makes no exception. Nevertheless it is true that the heir of the promisor is not held by such a bond alone, because, according to the primitive law of ownership, those things which belong to the commercial relations of life pass to the heir, but these do not include a right sought from God, as such.

This, again, must be repeated from an earlier statement, that if any one violates a sworn or unsworn pledge given to a brigand he will not on that account be liable to punishment among other nations. For because ‘of the hatred of brigands the nations have decided to overlook illegal acts committed against them.

VI.     The same rules are applicable in relation to rebellious subjects.
What shall we say regarding wars of subjects against their kings and other sovereign authorities?

That subjects do not have the right to employ force, even though they have a cause which in itself is not unjust, we have shown elsewhere. Sometimes even the injustice of their cause, or the baseness of their resistance, may be so great that they may be punished severely. Nevertheless, if they have been treated with as one would treat deserters or rebels, punishment cannot be inflicted contrary to a promise, as we have just stated.

In their scrupulousness the ancients held that faith must be kept even with slaves; in fact it was believed that the Lacedaemonians had drawn down upon themselves divine anger because they had killed the Taenarians, their slaves, contrary to agreement. Also Diodorus Siculus notes that the faith pledged to slaves at the shrine of the Palici had never been violated by any master. Moreover it will be possible to nullify here also the exception allowed in case a promise was made by reason of fear, if the promise has been confirmed by an oath; so the plebeian tribune, Marcus Pomponius,’ kept the promise which had been made to Lucius Manlius under the influence of fear, because he was bound by an oath.

VII.     The special difficulty presented by promises made to subjects under the right of eminent domain.
At this point, in addition to the difficulties previously met with, a special difficulty is presented by the right of passing laws and the right of eminent domain over the property of subjects; this right belongs to the state, and is exercised in its name by the one who holds supreme authority. If in fact this right covers all the possessions of subjects, why does it not cover also the right arising from a promise in war? If this be conceded, it appears that all such agreements will be void, and therefore there will be no hope of ending a war excepting through victory.

But, on the contrary, we must note that recourse is had to the right of eminent domain, not indiscriminately, but only in so far as this is to the common advantage in a civil government, which, even when regal, is not despotic. But in most cases it is to the common advantage that such agreements be kept; and what we have said elsewhere about the preservation of the existing government applies here also. An additional point is that, when circumstances demand the enforcement of this right, compensation ought to be given, as will be explained later.

VIII.     It is shown also that such promises may be confirmed by an oath of the state.
1.   Moreover treaties may be sanctioned by an oath taken not only by a king or a senate, but also by the state itself. Thus Lycurgus made the Lacedaemonians take oath to his laws, and Solon the Athenians; and in order that the oath might not become invalid on account of the change of persons it was repeated annually.

If such repetition is in fact kept up, there will be no necessity of withdrawal from the promise, even for the sake of the public advantage; for not only may a state yield its own right, but words can be made so clear as to admit of no exception. Valerius Maximus thus addresses Athens: ‘Read the law which holds you bound by oath.’ This kind of laws, by which the Roman people was itself in conscience bound, as Cicero explains in the speech For Balbus, the Romans called ‘sacred.”

2.   A rather obscure discussion bearing upon this subject is found in the third book of Livy, where he says that in the opinion of many interpreters of the law the tribunes were inviolable, but not likewise the ediles, judges, and decemvirs; yet, if harm should be done to any of the latter, an unlawful act was committed. The reason for the distinction is that the ediles and the others were protected by the law alone; moreover, what the people had voted last prevailed, and so long as the effect of the law lasted no one could lawfully act in opposition to it. The tribunes, on the contrary, were protected by a public religious obligation of the Roman people; for an oath had been taken which could not be annulled by those who had sworn it, without violating religious scruple. Dionysius of Halicarnassus says: ‘Brutus summoned an assembly and advised the citizens to make this magistracy inviolable, not only by law but also by an oath, and all so voted.’ That is the reason why the law is called sacred.

In consequence good men disapproved of the act of Tiberius Gracchus when he removed Octavius from the tribuneship, though he declared that the tribunician power received its inviolability from the people and not against the people. Therefore, as I have said, both a state and a king can be bound by an oath, even in the case of subjects.

IX.     Or, promises are binding if a third person, to whom the promise is made, enters into the case.
But also a promise will be made with binding force to a third person, who has not inspired fear. We shall not investigate how or to what extent he may be interested in the promise; these are subtle distinctions belonging to the Roman law. By nature, in fact, it is important for all men to have regard for other men. Thus we read that by the peace made with the Romans Philip was deprived of the right of visiting cruelty upon those Macedonians who had revolted from him in war.

X.     How the political character of a state may be changed.
Further, we have shown elsewhere that states of mixed character sometimes exist; and just as by agreement states may pass from one pure form into another, so they may pass also into a mixed form. Similarly those who had been subjects may begin to hold sovereign power, or at any rate some part of it, together with the free right to defend that part by force.

XI.     Fear does not justify an exception in respect to a war that is formal according to the law of nations.
1.   A formal war, that is a war publicly declared on both sides, has not only other characteristics in respect to legal right but also this characteristic in particular, that all promises made in the course of the war, or for the purpose of terminating it, are valid to the extent that they cannot be made void by reason of a fear unjustly inspired, except with the consent of the party to whom the promise has been made. For just as many other things, though they may not be devoid of fault in some degree, are considered lawful according to the law of nations, so also the fear which in such a war is inspired on both sides.

Unless this rule had been adopted, no limit nor termination could have been fixed for such wars, which are extremely frequent. Yet it is to the interest of mankind that such bounds be set. This may be understood to be that law of war which Cicero says must be observed with an enemy. Elsewhere Cicero declared that an enemy retains rights in war, obviously referring not only to rights arising from the law of nature, but also to certain rights which have arisen from the general consent of nations.

2.   From this nevertheless it does not follow that the party who has extorted some such promise by an unlawful war can retain what he has received without violating the honor and duty of a good man, or even can compel the other to hold to the agreement, whether sworn to or not. For essentially and in its nature the transaction remains unjust. This essential injustice of the action cannot be removed except through a new and absolutely free consent.

XII.     What is to be understood regarding such a fear as the law of nations recognizes.
But my statement that the fear inspired by a formally declared war is considered lawful ought to be understood of such a fear as is not disapproved by the law of nations. For if anything has been extorted by the fear of rape, or by terrorizing of any other sort which involves violation of pledged faith, it will be nearer the truth to say that the case has been brought within the scope of the law of nature; the force of the law of nations does not extend to such a fear.

XIII.     Faith must be kept even with the faithless.
1.   I have previously said, in the general treatment of promises, that faith must be kept even with the faithless. Ambrose, too, holds the same opinion; he thinks that beyond question the maintenance of good faith should be extended even to treacherous enemies, such as the Carthaginians, with whom the Romans kept faith inviolably. On this point Valerius Maximus remarks: ‘The Senate did not take into consideration those to whom the obligation was being discharged.’ Sallust, again, says: ‘ In all the Punic wars, although the Carthaginians both in time of peace and in periods of truce had committed many atrocious wrongs, the Romans themselves never took advantage of an opportunity to do such deeds.’

2.   Of the treaty-breaking Lusitanians, whom Sergius Galba had deceived by a new treaty and then slaughtered, Appian says ‘In avenging perfidy with perfidy he imitated the barbarians in a manner inconsistent with the dignity of Rome.’ On this charge the same Galba was afterward accused by the plebeian tribune Libo. In giving an account of the matter, Valerius Maximus says: ‘Pity and not justice ruled that trial, since the acquittal, which could not have been, granted to innocence, was given out of regard for his children.’ Cato had written in the Origins that Galba ‘would have been punished if he had not made use of his children and his tears.’

XIV.     Faith does not have to be kept if the condition changes; and this takes place if the other does not keep his part of the agreement.
At the same time the fact should be recognized that in two ways one may be free from breach of faith and yet not do what was promised if the condition ceases, and if compensation is given. The cessation of the condition does not in reality free the promisor, but the result shows that there is no obligation, since this was entered into only under the condition.

To this principle we must refer the case which arises if the other party has not fulfilled what he on his part was bound to carry out. For the individual items of one and the same agreement seem to be related in respect to the two sides after the manner of a condition, as if it had been stated in this way: I will do thus and so if the other does what he has promised. Thus Tullus, replying to the Albans, ‘calls the gods to witness, which of the two peoples first rejected and dismissed the envoys demanding restitution, in order that they may visit on that people all the losses of the war.’ Ulpian says: ‘He’ will not be liable as a partner who has renounced a partnership for the reason that a certain condition, on which the partnership was formed, is not complied with in relation to him.’ For this reason, whenever the intent is different, it is usually expressly stated that if anything is done contrary to this or that provision the others nevertheless will remain valid.

XV.     Faith does not have to be kept in case a just compensation is tendered in return.
The origin of compensation I indicated elsewhere,’ when I said that if anything is ours or is due to us, and we cannot otherwise obtain it from him who has it or owes it to us, we can accept an equivalent amount in something else. From this it follows the more clearly that we may keep what is in our possession, whether it be corporeal or incorporeal. Therefore what we have promised will not have to be fulfilled if the value involved is no greater than that of our property which is wrongfully in the possession of the other.

In the sixth book On Benefits Seneca says:

So a creditor often loses his suit to his debtor when on another account he has taken more than he tries to secure from the debt. For the judge sits between the creditor and the debtor to say, ‘You have loaned him money; what then? . . . You have possession of a field which you did not buy; after an adjustment of values, you, who came as a creditor, depart as a debtor.’

XVI.     Faith does not have to be kept in case a just compensation is tendered in return, even if this is on another contract.
The same principle will hold if the party with whom I have dealings owes as much or more under another agreement, and I am not able otherwise to secure what is due to me. In the law courts, as the same Seneca says,’ different actions are separated, and the causes of action are not mixed. But, as noted in the same passage, those cases are guarded by definite statutes which it is necessary to observe: a law must not be mixed with a law; we must go whither we are led. The law of nations does not recognize those distinctions; in the cases which fall within its scope there is no other hope of acquiring one’s right.

XVII.     Faith does not have to be kept in case damage has been done.
The same principle will have to be applied if the party who insists on the fulfilment of a promise has not carried out his part of the agreement, but has inflicted damage. In the passage just cited Seneca says: ‘A landowner who has trampled down the crop or cut down the trees of his tenant has no legal right over the tenant, even though the lease is uncancelled, not because he has received what had been agreed upon, but because he himself was the cause of his not receiving it.’ Presently Seneca adds other examples ‘You have driven away his cattle and killed his slave.’ And again: ‘It is permissible for me to compare how much each one has assisted me, how much he has injured me, and then to declare whether he is more indebted to me or I to him.’

XVIII.     Furthermore, faith does not have to be kept when something is due as a penalty.
Finally, what is due as a penalty can be taken in lieu of what has been promised. This is explained at length in the passage already quoted: ‘On the one hand favor is due for a benefit, on the other vengeance for an injury. Gratitude is not due to him from me, nor punishment to me from him; the indebtedness on both sides is cancelled.’ Presently Seneca adds: ‘ After a comparison has been made between the favors and the injuries, I shall see whether anything more is due to me.’

XIX.     How these principles become applicable in war.
1.   just as in case an agreement has been made between contesting parties, while the suit is in progress, neither the action which gave rise to the suit, nor the losses and damages of the suit, can be used as an offset for what was promised, so, while a war lasts, compensation cannot be given for what originally caused the war, nor for what is customarily arranged in accordance with the laws of war among nations. For the nature of the business, that it be not void of effect, shows that the agreement was made without consideration of the controversies which led to the war. Otherwise, in fact, there would be no agreement which could not be lightly set aside.

To this conclusion I may not inaptly apply the observation of the same Seneca, whom I have several times quoted: ‘ Our ancestors accepted no excuse, in order that men might know that good faith must by all means be preserved. It was in fact better that even a just excuse from a few should not be accepted, than that any sort of an excuse should be tried by all.’

2.   What, then, can be used as an offset to that which was promised? Undoubtedly whatever the other party owes, even under the terms of another agreement entered into during the war; or, it may be reckoned as an offset if he has caused damage during a truce, or has failed to respect the inviolability of ambassadors, or has done anything else which the law of nations condemns between enemies.

3.   Nevertheless the observation should be made that the adjustment is arranged between the same parties, and in such a way that the right of a third party is not infringed; yet so that the goods of subjects, as we have said elsewhere, are held by the law of nations to be liable for the debt which the state owes.

4.   We add this also, that it is characteristic of a noble mind to abide by treaties even after an injury has been suffered. For this reason the wise Hindu Iarchas praised the king who, although wronged by an allied neighbor, ‘did not withdraw from his sworn pledge, saying that he had sworn in so holy a manner that he would not harm the other even after suffering wrong.’

5.   Almost all the questions which are wont to arise concerning the faith accorded to an enemy can be settled if we follow the rules already laid down in our discussion not only of the force of promises of all kinds, or of a special oath, or of a treaty and sponsions, but also of the rights and obligations of kings, and the interpretation of ambiguous statements. Nevertheless, in order that the application of the foregoing principles may be more plain, and that our discussion may be extended to cover whatever else is in dispute, I shall not hesitate to touch on the special questions which are more common and which more generally demand attention.