Natural Law and Peace: A Biography of Hugo Grotius
Hugo Grotius, a 17th century Dutch legal scholar and philosopher, was the father of modern international law and a staunch opponent of war.
For centuries, rulers had pursued wars to spread their religion, gain territory, seize assets or in other ways expand their power. The Florentine political thinker Niccolo Machiavelli had described war as a perfectly legitimate government policy.
Then the early 17th century Dutch legal scholar and philosopher Hugo Grotius declared that war was wretched and that it harmed all participants. If war can’t always be avoided, Grotius pleaded that at least the killing and destruction must be limited. He believed “it is folly, and worse than folly, wantonly to hurt another…War is a matter of gravest importance, because so many calamities usually follow in its train, even upon the head of the innocent. So, where counsels conflict we ought to incline toward peace…It is often a duty, which we owe to our country and ourselves, to forbear having recourse to arms…[the] conquered should be treated with clemency, in order that the interests of each may become the interests of both.”
Historian John Neville Figgis observed, “The danger of Machiavelli was not that he dissected motive and tore the decent veil of hypocrisy from statesmen, but that he said or implied that these facts were to be the only ideal of action; the service of Grotius, his forerunners and successors is…that they succeeded in placing some bounds to the unlimited predominance of ‘reason of state.’”
Grotius originated international law as we know it, refining principles to help improve the prospects for peace. He declared: “On whatever terms peace is made, it must be absolutely kept, from the sacredness of the faith pledged in the engagement, and every thing must be cautiously avoided, not only savoring of treachery, but that may tend to awaken and inflame animosity.”
Biographer Liesje van Someren explained, “Grotius’ great aim was to develop, and insist upon, the idea of justice among nations. With that in mind, he hoped that the widest international differences could be met, if not by the parties themselves then by mediators, arbitrators, or international conferences. If the world would only follow Grotius’ rules and principles, war may become less frequent, and less horrible.”
Grotius championed a natural law philosophy which derived from the “higher law” doctrine of Marcus Tullius Cicero and other ancient Roman and Greek philosophers. They believed the legitimacy of government laws must be judged by standards of justice – natural law. Grotius defended natural law without appealing to the Bible or organized religion. He insisted it followed from the nature of things, and it was discovered by human reason. He wrote, “Now the Law of Nature is so unalterable, that it cannot be changed even by God himself. For although the power of God is infinite, yet there are some things, to which it does not extend.”
Natural law, Grotius maintained, is the basis of natural rights: “Civilians call a faculty that Right, which every man has to his own…This right comprehends the power, that we have over ourselves, which is called liberty…It likewise comprehends property…Now any thing is unjust, which is repugnant to the nature of society, established among rational creatures. Thus for instance, to deprive another of what belongs to him, merely for one’s own advantage, is repugnant to the law of nature.” In the process of working out these ideas, as intellectual historian Murray N. Rothbard pointed out, Grotius “brought the concepts of natural law and natural rights to the Protestant countries of northern Europe.”
All his life, Grotius displayed an extraordinary passion for knowledge. He was considered a child prodigy. He achieved impressive things as a young man. He managed to continue learning when he was in prison. His most famous work, De Jure Belli ac Pacis [The Law of War and Peace] was written when he was an impoverished refugee, and it cited about 120 ancient authors (Cicero was his favorite). Grotius’ learning helped him make friends among Catholics and Protestants, although Catholics and Protestants were killing each other.
He had the misfortune of being a Protestant persecuted by Protestants because he defended the view that human beings have free will. No wonder van Someren reported: “His friends found him often moody and irritable, and not as tactful as he might have been; yet they all liked him. His own family were devoted to him despite the fact that he was sometimes inconsiderate and quarrelsome.”
Grotius was apparently an impressive‐looking man, tall and handsome. “His features were finely chiseled,” wrote biographer Hamilton Vreeland, “his nose slightly aquiline, his eyes blue and sparkling, his hair brown. His person was tall and well formed. Active both in mind and in body…”
Grotius influenced the English natural rights philosopher John Locke. The Scottish economist and philosopher Adam Smith observed, “Grotius seems to have been the first who attempted to give the world anything like a regular system of natural jurisprudence, and his treatise [De Jure Belli ac Pacis], with all of its imperfections, is perhaps at this day the most complete work on the subject.” Thomas Jefferson and James Madison considered Grotius a leading authority on resolving international disputes. Lord Acton declared, “It would be easy to point out…a sentence of Grotius that outweighs in influence the Acts of fifty Parliaments…”
Historian John U. Nef wrote, “What is most significant for subsequent history in his work on war and peace is the insistence that legal principles exist in the human reason, independent of any actual worldly authority, political or religious, yet binding in the world – principles which should govern in all contingencies arising out of breaches of the peace between sovereign states. Before recourse to arms, a country should make a formal declaration of its grievances, and should go to war only if satisfaction could not be obtained through diplomatic negotiations. Wars should be fought according to accepted rules providing for humane treatment of the wounded and the prisoners. Treaties ending wars should also be drawn according to accepted rules which, in effect, precluded the conquest of one of the antagonists by the other and the subjugation of the enemy population.”
Huig van Groot, Latinized to Hugo Grotius, was born in Delft, Holland, April 10, 1583. He was the oldest of four children, the son of Jan de Groot and Alida van Oerschie. Jan de Groot was a lawyer and a trustee of the University of Leyden.
This was a perilous time. In 1568, Protestants in the seven northern Dutch provinces began their struggle for independence from Spain whose Catholic King Philip II pursued religious intolerance and high taxes. The Dutch, fortunately, were served by able leaders, beginning with William of Orange (William the Silent) and after his death, his second son William of Nassau in partnership with the lawyer Johan van Oldenbarnevelt. William of Nassau proved to be a resourceful military commander, while Oldenbarnevelt kept the provinces politically together.
When Grotius was 11, he entered the University of Leyden. He studied Greek and Roman history, philosophy, mathematics, astronomy, law and religion. As a student, he lived in the home of Franciscus Junius who passionately believed in religious toleration and peace. Grotius studied for a year in France, earning a Bachelor of Laws degree at the University of Orleans.
Back in Holland, Grotius was sworn in as a lawyer on December 1, 1599. His father arranged for him to begin practice with a government official. He wrote a book on logic and translated a work about using the compass. In 1601, the United Provinces asked 18‐year‐old Grotius to write the history of their valiant struggle against Spain.
Around 1604, the Dutch East India Company, formed to handle Dutch trade in the Indian Ocean, asked Grotius for a brief explaining why they ought to be able to do business with territories claimed by the Portuguese. He made a case that everybody had the right to use an ocean, regardless who explored it. The Dutch East India Company decided against publishing the brief, De Jure Praedae [The Law of Spoils], and it didn’t come to light until discovered in The Hague more than two and a half centuries later.
While visiting Veere, Zeeland with his lawyer friend Nicholaas van Reigersbergen, Grotius stayed at the home of Reigersbergen’s parents and met his beautiful, self‐assured 18‐year‐old sister Maria. She fell for Grotius right away. Her father recognized marriage possibilities and began negotiations with Hugo’s father. The wedding took place sometime in mid‐July 1608. They were to have six children: Cornelius, Pieter, Diederic, Frances, Mary and Cornelia.
The Dutch East India Company asked Grotius for a book about freedom of the seas, and he submitted the twelfth chapter of De Jure Praedae, which was published as Mare Liberum [The Free Sea]. Grotius drew on Mare Liberum when he prepared a brief against Britain’s King James I who banned foreigners from fishing in the waters around Britain and Ireland. Grotius wrote: “No prince can challenge further into the sea than he can command with a cannon, except gulfs within their land from one point to another.” Cannon‐shot range – about three miles – became an international standard defining territorial waters.
Grotius became a good friend of Jacobus Arminius, a University of Leyden theology professor who believed that individuals have free will. Arminius disputed the prevailing Calvinist doctrine of predestination, that God determines what everybody’s fate will be, regardless of how virtuous they are. Arminius believed anybody could achieve eternal happiness with faith.
Arminius died on October 19, 1609, at 49, but controversy intensified, and Grotius tried to resolve issues peacefully. Elder statesman Johan van Oldenbarnevelt proposed that city officials should be able to raise armed forces for maintaining order. On August 29, 1618, Grotius, Oldenbarnevelt and compatriot Gillis van Ledenberg were arrested – although the particular charge wasn’t specified. A special tribunal of 24 judges was set up to hear these cases. Guilty verdicts were a foregone conclusion. Ledenberg, fearing torture, stabbed himself in the stomach and cut his throat. Oldenbarnevelt – a Founder of the United Provinces — was convicted of treason and beheaded. Grotius feared the same fate, but on November 19, 1618 he drew a sentence of life imprisonment and forfeiture of all his goods. Soldiers escorted him to the massive fortress of Loevestein, near Gorcum, with two moats and walls about six feet thick. Grotius was kept in a two‐room cell.
Nine months into his sentence, Grotius’ wife Maria was given permission to visit him, and he was allowed to get books from the library of his friend Adrian Daatselaer, a ribbon and thread merchant. The books were brought from Daatselaer’s house to the prison in a trunk about four feet long. When Grotius was through, he sent the trunk back so it could bring him more books. Grotius translated some Greek and Latin tragedies into Dutch. He wrote The Truth of the Christian Religion which was later translated into Arabic, Chinese, Danish, English, Flemish, French, German, Greek, Persian and Swedish. Ironically, since his trial had violated principles of Dutch law, he wrote Introduction to the Jurisprudence of Holland.
Security procedures were relaxed, soldiers didn’t bother checking the trunk as it passed back and forth, Grotius escaped in it on March 22, 1621. It was accompanied by their 20‐year‐old maid, Elsje van Houwening. Several times, soldiers expressed suspicion because of the unusual weight of the trunk. Elsje assured them it was filled with Arminian books. After arriving at Daatselaer’s house, Grotius dressed in stonemason’s clothes and fled to France. Daatselaer, Maria and Elsje were grilled, but nothing could be proven against them.
Some of Europe’s best‐known poets celebrated his escape to freedom and the brave wife and friends who helped him. Maria joined him by September. However, his assets had been seized, and he didn’t have many prospects for immediate income.
Amidst poverty and debts, he produced Justification of the Lawful Government of Holland and West Friesland which attacked the proceedings against him. He wrote that he had been denied an opportunity to defend himself and that it wasn’t true, as officials claimed, that he had confessed to crimes; he said he had never been interrogated, and he didn’t know what the alleged crimes were about. He affirmed his belief that toleration was better than persecution. The work was published in Amsterdam, November 1622, and it outraged the States‐General. They denounced him for what they called “a notorious, seditious and scandalous Libel” and declared that anybody caught possessing or reading a copy of Grotius’ work would be punished.
When a plague epidemic broke out, Grotius moved to the countryside, and he accepted an offer to live at a friend’s house near Senlis. Here, in 1623, he began work on De Jure Belli ac Pacis. He took the title from a phrase in Marcus Tullius Cicero’s Oratio pro Balbo. He expanded on the ideas and organization which he had used in De Jure Praedae, the unpublished brief written more than 20 years before — a draft of which he had with him. Grotius was able to work rapidly because another friend made available a big library. Grotius finished the book in about a year. It appeared in Paris, June 1625. The printer paid Grotius by giving him 200 copies of the book..
“I am convinced,” Grotius wrote, “that there is some law common to all nations, which applies both to the initiation of war and to the manner in which war should be carried on. There were many and weighty considerations impelling me to write a treatise on the subject of law. I observe everywhere in the Christian world a lawlessness in warfare, of which even barbarous nations would be ashamed. And arms once taken up, there would be an end to all respect for law, whether human or divine, as though a fury had been let loose with general license for all manner of crime.”
While Grotius was influenced by Thomas Aquinas, Francisco Suarez and other Scholastic thinkers, he developed principles of justice independent of organized religion or the Bible. He believed nations should be guided by natural law. This meant “the dictate of right reason showing the moral turpitude, or the moral necessity, of any act from its agreement or disagreement with a rational nature…”
Grotius didn’t follow the logic of natural law all the way. He accepted slavery even though this obviously violated the natural principle that individuals own themselves. Grotius didn’t see all the radical implications of natural rights.
Grotius recognized the right of self‐defense and the right to be compensated for injuries inflicted by an adversary, but especially in Book III, he encouraged restraint. He believed that everything should be done to resolve disputes peacefully, because all sides are sure to suffer grievous losses from war. He advised limiting what might be seized from an adversary. He wrote, “The law of nature indeed authorizes our making such acquisitions in a just war, as may be deemed an equivalent for a debt, which cannot otherwise be obtained, or as may inflict a loss upon the aggressor, provided it be within the bounds of reasonable punishment.” Similarly, he insisted that retaliation “must be directly enforced upon the person of the delinquent himself.”
De Jure Belli ac Pacis provoked plenty of controversy. Catholics were shocked because Grotius didn’t refer to the Popes by their Catholic titles. Accordingly, De Jure Belli ac Pacis was placed on the Papal Index in March 1626, and Catholics were forbidden to read it. The book remained on the Papal Index until 1901.
Grotius hoped that the fame he gained from De Jure Belli ac Pacis would overcome hostility in the Netherlands. He went to Rotterdam and visited a statue of Erasmus which had been put up while he was away. Officials issued an order for his arrest, and he fled on March 17, 1632. He headed for Hamburg because it was reasonably close to Sweden whose king, Gustavus Adolphus, was emerging as the leading Protestant champion and might possibly retain his services.
Grotius was miserable in Hamburg. He was broke. He didn’t meet any intellectually interesting people, and he wasn’t able to find a library where he could work. Gustavus Adolphus was killed in the Battle of Luetzen, November 1632, and was succeeded by his six‐year‐old daughter Maria Christina. The Regent was Axel Oxentierna who had more important things to think about than Grotius. Then another blow: Grotius’ son Cornelis was killed in battle.
Things began to look up in 1634. Largely on the strength of the knowledge and wisdom displayed in De Jure Belli ac Pacis, Grotius was asked to be Sweden’s ambassador to France. Grotius’ money worries were over. He helped promote peace between Sweden and France.
He was sick when he retired in 1645. He boarded a ship which got caught in a storm and came ashore on the Pomeranian coast, northern Germany east of Denmark. He was carried by farm cart about 60 miles to Rostock. He arrived quite frail at a lodging house on August 26, 1645. He asked for a minister, and the only one available was John Quistorpius, a Lutheran. Quistorpius remained by Grotius’ side and heard his despairing last words: “By undertaking many things I have accomplished nothing.”
He died around midnight, August 28th at 62. According to biographer Charles Edwards, “The vital organs were removed from Grotius’ body, sealed in a copper container, and buried in the cathedral at Rostock. His mortal remains were sent to Delft where they were entombed in the Nieuwe Kerk, or New Church, situated on the public square. Ironically, Grotius was laid to rest amidst the tombs of the princes of Orange, one of whom had compelled him to live for so many years as a fugitive from justice.”
The Thirty Years’ War, which had raged since 1618, continued for another seven years. “Physically Germany was wrecked,” reported historian Robert R. Palmer. “Cities were sacked by mercenary soldiers with a rapacity that their commanders could not control; or the commanders themselves, drawing no supplies from their home governments, systematically looted whole areas to maintain their armies…The effects of fire, disease, undernourishment, homelessness, and exposure in the seventeenth century were the more terrible because of the lack of means to combat them.”
All this added urgency to Grotius’ views about peace. Biographer W.S.M. Knight reported that “During the century succeeding the first publication [of De Jure Belli ac Pacis] edition after edition issued from the press, almost always in Germany or Holland, at the rate of about one in every third year.” Gradually, though, people came to rely on more recent works. By the 20th century, according to professor Steven Forde in American Political Science Review, Grotius’ “reputation suffered a severe decline due to the rise of positivism in international law and the disfavor of natural law thinking in moral philosophy.” Positivist thinkers insisted that whatever government does is okay as long as it’s legal. But the positivist view was discredited when 20th century governments murdered tens of millions legally. This brought renewed interest in Grotius, and there are many Grotius sites on the Internet.
Grotius courageously spoke out against war, one of the worst evils. He upheld moral standards independent of rulers. He told how to improve the prospects for peace. The greatest peace settlements, like those ending World War II and the Cold War, displayed his wisdom and generous spirit as they helped turn enemies into friends.