The philosophy of Hugo Grotius

GROTIUS'S first publication was the Mare Liberum (1609), asserting the freedom of the seas. His monumental work De Jure Belli et Pacis (The Rights of War and Peace) was published in 1625. An earlier work on this subject was a treatise On the Law of Spoil, written in 1604 but not published until 1868. He also wrote on theology, and his Annals of the Netherlands is the best contemporary account of the revolt against Spain. But it was the De Jure which made Grotius one of the great jurists of the world. It laid the foundations of modern international jurisprudence by the endeavour to weigh the often conflicting claims of law and morality as applied to the conduct of state towards state.


BEING fully assured that there is some right common to all nations which takes place both in the preparations and in the course of war, I had many and weighty reasons inducing me to write a treatise upon it. I observed through the Christian world a licence in regard to war of which even barbarians ought to be ashamed. I observed people rush to arms upon frivolous, or, rather, no occasions at all; and once arms were taken up, good-bye to any reverence for law, whether divine or human. It was just as if a single declaration of war had liberated madness to commit all manner of crimes.

The spectacle of such monstrous barbarism brought many, and those in no wise ill men, to hold that a Christian, whose duty consists principally in loving all men, ought to be forbidden the use of arms. With them appear sometimes to agree Johannes Ferus and our countryman, Erasmus, men that were great lovers of peace both ecclesiastical and civil. But I suppose they had the same view as those have who, in order to make things that are crooked straight, usually bend them as much the other way. A cure must be applied as well to prevent believing that nothing, as that all things, is lawful.

Let the laws, then, be silent in the midst of arms; but only those laws that are civil and judicial, and proper for times of peace, not those other laws that are perpetual of obligation and suited to all times. For it was well said by Dion of Prusa [Chrysostom] that between enemies the written--that is, civil--laws are of no force, but the unwritten are; that is, those which nature dictates or the consent of nations has instituted. This is shown in that ancient formula of the Romans, 'My view is that these things must be recovered by a pure and just war.' The Romans, as Varro observed, also were slow in entering upon war, because they thought no war except a just one should be carried on. It was a saying of Camillus that wars ought to be managed with as much justice as valour, and of Scipio Africanus that the Roman people began and ended their wars with justice. You can read in another author, 'There are laws of war, as there are laws of peace.'

[Method of Investigation]

WHAT method we thought fit to use we have shown in fact rather than in theory in this treatise. It handles far the noblest part of jurisprudence. For in the first book, after premising some things concerning the origin of right, we have examined the general question whether any war is just. Afterwards, to discover the difference between a public and a private war, our business was to explain the extent of the supreme power, what people, what kings have it in full, who in part, who with a power of alienating it, and who have it without that power. And then we had to expound the duty of subjects to sovereigns.

The second book, undertaken to explain all the causes whence war may arise, shows at large what things are common, what personal, what right one person may have over another, what obligation arises from ownership, what is the rule of legal succession, what right accrues from covenant or contract, what the force and interpretation of treaties, what of an oath, both public and private, what may be due for damage done, what are the privileges of ambassadors, what the right of burying the dead and what the nature of punishments.

The third book has for its first subject-matter what is lawful in war. Then, having distinguished that which is done with bare impunity, or which is even defended as lawful among foreign nations, from that which is really blameless, it descends upon the several kinds of peace and all conventions concluded in war.

My first care was to refer the proofs of those things that belong to the law of nature to some such certain notions as none can deny without doing violence to his judgement. For the principles of that law, if you rightly consider, are manifest and self-evident, almost after the same manner as those things are that we perceive with our outward senses, which do not deceive us if the organs are rightly disposed and if other things necessary are not wanting.

I have likewise, towards the proof of this law, made use of the testimonies of philosophers, historians, poets and, in the last place, orators; not as if they were to be implicitly believed without enquiry; but that when men of different times and places unanimously affirm the same thing for truth, this ought to be ascribed to a general cause, which in the questions treated of by us can be no other than either a just inference drawn from the principles of nature, or an universal consent. One shows the law of nature, the other the law of nations.

Return to Outline of Great Books Volume I