The Principles of Natural and Politic Law (1748)

Jean Jacques Burlamaqui

Of compacts made with an enemy.

I. AMONG public compacts, those, which suppose a state of war, and are made with an enemy, deserve particular attention. Of these there are two kinds; some, which do not put an end to the war, but only moderate or suspend the acts of hostility; and others, which end the war entirely. But before we consider these compacts in particular, let us inquire into the validity of them in general.

Whether we ought to keep our faith given to an enemy?

II. This question is certainly one of the most curious and important, belonging to the law of nations. Grotius and Puffendorf are not agreed in this point. The former maintains, that all compacts, made with an enemy, ought to be kept with an inviolable fidelity. But Puffendorf is somewhat dubious with respect to those compacts, which leave us in state of war, without a design to remove it. Let us therefore endeavour to establish some principles, by means of which we may determine with respect to these two opinions.

III. I observe, 1. That though war of itself destroys the state of society between two nations, we must not thence conclude that it is subjected to no law, and that all right and obligation are absolutely at an end between enemies.

2. On the contrary, every body grants that there is a right of war, obligatory of itself, between enemies, and which they cannot violate, without being defective in their duty. This is what we have proved before by showing, that there are just and unjust wars; and that, even in the justest, it is not allowable to push acts of hostility to the utmost extremity, but that we ought to keep within certain bounds; and consequently, that there are things unjust and unlawful, even with respect to an enemy. Since therefore war does not, of itself, subvert all the laws of society, we cannot from this alone conclude, that, because two nations are at war with each other, they are dispensed from keeping their word, and from fulfilling the engagements they have made with each other, during the course of the war.

3. As war is in itself a very great evil, it is the common interest of nations not to deprive themselves voluntarily of the means, which prudence suggests to moderate the rigor, and to suspend the effects of it. On the contrary, it is their duty to endeavour to procure such means, and to make use of them upon occasion; so far at least, as the attainment of the lawful end of war will permit. Now there is nothing but public faith, that can procure to the parties, engaged in war, the liberty to take breath; nothing but this can secure to towns, that have surrendered, the several rights, which they have reserved by capitulation. What advantage would a nation gain, or rather, what is it they would not lose, if they were to have no regard to their faith, given to an enemy, and if they looked upon compacts, made in such circumstances, only as the means of circumventing one another? Surely it is not to be supposed that the law of nature approves of maxims so manifestly opposite to the common good of mankind. Besides, we ought never to wage war, merely for the sake of it, but only through necessity, in order to obtain a just and reasonable satisfaction, and a solid peace; whence it evidently follows, that the right of war between enemies cannot extend so far, as to render hostilities perpetual, and to create an invincible obstacle to the reestablishment of the public tranquillity.

4. And yet this would certainly be the consequence, if the law of nature did not lay us under an indispensable obligation of performing whatever agreement we have voluntarily made with the enemy during the war; whether these agreements tend only to suspend, or moderate acts of hostility, or whether they are designed to make them cease entirely, and to reestablish peace.

For in short there are only two ways of obtaining peace. The first is the total and entire destruction of our enemy; and the second is the entering into articles of treaty with him. If therefore treaties and compacts, made between enemies, were not in themselves sacred and inviolable, there would be no other means of procuring a solid peace, than carrying on the war to the utmost extremity, and to the total ruin of our enemies But who does not see that a principle, which tends to the destruction of mankind, is directly contrary to the law of nature and nations, whose principal end is the preservation and happiness of human society?

5. There is no distinction, in this respect, between the different treaties, that we may enter into with an enemy; for the obligation, which the laws of nature lay upon us, to observe them inviolably relates as well to those, which do not put an end to the war, as to those, which tend to reestablish peace. There is no medium, and we must lay it down as a general rule, that all compacts with an enemy are obligatory, or that none of them are really such.

And indeed, if it were lawful for instance to break a solemn truce, and to detain, without any reason for it, people, to whom we had given passports, etc. what harm would there be in circumventing an enemy, under a pretext of treating of peace? When we enter into a negotiation of this kind, we are still enemies; and it is properly but a kind of truce, which we agree to, in order to see if there be any means of coming to an accommodation. If the negotiations prove unsuccessful, it is not then a new war, which we begin, since the differences, that occasioned our taking up arms, are not yet adjusted; we only continue the acts of hostility, which had been suspended for some time; so that we could no more rely on the enemy’s sincerity, with respect to compacts, which tend to reestablish peace, than to those, whose end is only to suspend, or moderate acts of hostility. Thus distrusts would be continual, wars eternal, and a solid peace unattainable.

6. The more frequent unnecessary wars are become, through the avarice and ambition of sovereigns, the more a steady adherence to the principles, here established, is indispensably necessary for the interest of mankind. Cicero therefore justly affirms, that there is a right of war, which ought to be observed between the contending parties, and that the enemy retains certain rights, notwithstanding the war.1

Nor is it sufficient to say, as Puffendorf does, that it is a custom, which, among others, has obtained among civilized nations, out of particular respect to military bravery, that all compacts made with an enemy ought to be looked upon as valid. He should also have added, that this is an indispensable duty, that justice requires it, that it is not in the power of nations to establish things on another footing, and that they cannot justly deviate from the rules, which the law of nature prescribes, in this case, for their common advantage.

IV. It will not be difficult, by means of the principles here established, to answer the arguments, by which Puffendorf pretends to show, that all compacts, made with an enemy, are not of themselves obligatory. We shall be content with observing, 1. that those arguments prove nothing, because they prove too much, etc. and 2. all, that can be concluded from them, is, that we ought to act prudently, and take proper precautions before we pass our word, or enter into any engagement with an enemy; because mankind are apt to break their promises for their own interest, especially when they have to deal with people, whom they hate, or by whom they are hated.

V. But it will be said, is it not a principle of the law of nature, that all conventions and treaties, extorted by injustice and violence, are void of themselves; and consequently, that he, who has been forced to make them against his will, may lawfully break his word, if he thinks he can do it with safety?

Violence and force are the characteristics of war; and it is generally the conqueror, that obliges the vanquished to treat with him, and by the superiority of his arms, constrains them to accept the conditions he proposes to them, whether the war he has undertaken be just or not. How then is it possible, that the law of nature and nations should declare treaties, made in those circumstances, to be sacred and inviolable?

I answer, that however true the principle, on which this objection is founded, may be in itself, yet we cannot apply it, in all its extent, to the present question.

The common interest of mankind requires, that we should make some difference between promises, extorted by fear, among private persons, and those, to which a sovereign prince or people is constrained, by the superiority of the arms of a conqueror, whose pretensions were unjust. The law of nations then makes an exception here to the general rule of the law of nature, which disannuls conventions, extorted by unjust fear; or, in other words, the law of nations holds for just on both sides that dread or apprehension, which induces enemies to treat with each other, during the course of a war, for otherwise, there would be no method, either of moderating its fury, or of putting a final period to it, as we have already demonstrated.

VI. But, that nothing may be omitted, relating to this question, we shall add something for the further illustration of what we have been saying.

First then, it is necessary I think to distinguish here, whether he, who by the superiority of his arms has compelled his enemy to treat with him, had undertaken the war without reason; or whether he could alledge some specious pretext for it. If the conqueror had undertaken the war for some plausible reason, though perhaps unjust at bottom, then it is certainly the interest of mankind, that the law of nations should make us regard the treaties, concluded in such circumstances, as valid and obligatory; so that the conquered cannot refuse to observe them under a pretext, that they were extorted by an unjust fear.

But if we suppose, that the war was undertaken without reason, or if the motive alledged be manifestly frivolous or unjust, as Alexander’s going to subdue remote nations, who had never heard of him, etc. as such a war is a down right robbery, I confess I do not think the vanquished more obliged to observe the treaty, to which they were compelled, than a man, fallen into the hands of thieves, is bound to pay a sum of money, which he had promised them, as a ransom for his life or liberty.

VII. We must also add, as a very necessary remark, that even supposing the war was undertaken for some apparent and reasonable cause, if the treaty, which the conqueror imposes on the vanquished, includes some condition manifestly barbarous, and entirely contrary to humanity; we cannot, in those circumstances, deny the vanquished a right of receding from their engagement, and of beginning the war afresh, in order to free themselves, if they can, from the hard and inhuman conditions, to which they were subjected, by the abuse their enemy nude of his victory, contrary to the laws of humanity. The justest war does not authorize the conqueror to keep no measures, or to use all liberties with respect to the vanquished; and he cannot reasonably complain of the breaking of a treaty, the conditions of which are both unjust in themselves, and full of barbarity and cruelty.

VIII. The Roman history furnishes us with an example to this purpose, which deserves our notice.

The Privernates had been several times subdued by the Romans, and as often revolted; but their city was at last retaken by the consul Plautius. In these distressed circumstances, they sent ambassadors to Rome to sue for peace. Upon a senator’s asking them what punishment they thought they deserved; one of them answered, that, which is due to men, who think themselves worthy of liberty. Then the counsel asked them, whether there was any room to hope, that they would observe the peace, if their faults were pardoned? “The peace shall be perpetual between us, replied the ambassador, and we shall faithfully observe it, if the conditions you lay upon us are just and reasonable; but if they are hard and dishonorable, the peace will not be of long continuance, and we shall very soon break it.”

Though some of the senators were offended at this answer, yet most of them approved of it, and said, that it was worthy of a man, and of a man, who was born free; acknowledging therefore the rights of human nature, they cried out, that those alone deserved to be citizens of Rome, who esteemed nothing in comparison of liberty. Thus the very persons, who were at first threatened with punishment, were admitted to the privilege of citizens, and obtained the conditions they wanted; and the generous refusal of the Privernates to comply with the terms of a dishonorable treaty gained them the honor of being incorporated into a state, which at that time could boast of the bravest, and roost virtuous subjects in the universe.2

Let us therefore conclude, that a due medium is to be observed; that we ought inviolably to observe treaties made with an enemy, and that no exception of an unjust fear should authorise us to break our promise, unless the war was a downright robbery, or the conditions imposed on us were highly unjust, and full of barbarity and cruelty.

IX. There is still another case, in which we may avoid the crime of perfidiousness, and yet not perform what we have promised to an enemy; which is, when a certain condition, supposed to be the basis of the engagement, is wanting. This is a consequence of the very nature of compacts; by this principle, the infidelity of one of the contracting parties sets the other at liberty; for, according to the common rule, all the articles of the same agreement are included one in the other, in the manner of a condition, as if a person were expressly to say, I will do such or such a thing, provided you do so or so.3


   1.     Est etiam jus bellicum; fidesque jurisjurandi sæpe cum hoste servanda. Off. lib. iv. cap. 29.
   2.    Livy lib. viii, cap. xx, xxi.
   3.    See above.