Hugo Grotius: Father of International Law

Hugo Grotius: Father of International Law

Huig de Groot was born in Holland in 1583. He graduated from the University of Leiden at fourteen years of age and received the degree of Doctor of Law from the University of Orleans two years later.

In 1609 he published his first work on international law, a treatise in defense of freedom of the seas (Mare Liberum), which was actually a chapter in a larger unpublished work titled Commentary on the Law of Prize. He conceived his most important work. The Law of War and Peace, while he was in prison on political charges, and he wrote it between 1623 to 1625, following his escape to France.


Rightly regarded as the father of international law, Grotius’s extensive influence and many contributions to the science of jurisprudence defy summarization here. We can, however, examine the rules for the conduct of war that he formulated, articulated, and systematized, and we can explain why those rules were so suited to the needs of his world and how they are relevant to our world today.

To prepare the way for that examination and analysis, we will profit from putting Grotius’s work in the context of his time, noting the relationship between morality and law in his theory of jurisprudence and understanding his theory of international law.

During the Middle Ages, the international order of Europe rested primarily Church. With the Church as the dominant central authority-for matters political as well as spiritual-international legal questions were seen as subjective moral determinations in the Augustinian tradition, rather than objective empirical issues as they had been in the Roman tradition. But Grotius confronted a society marked by (1) the replacement of feudal systems with national states, (2) the increase in world trade and colonialism, and (3) the fragmentation of the Christian Church.

Without a powerful ecclesiastical authority to mediate and arbitrate interests between increasingly powerful states, many of them with worldwide expansionist and trade interests, force became a common medium of political intercourse. National animosities that had been held in check for centuries by a unity of religion found expression on the battlefield.

A particularly abominable outcome of the new societal conditions, namely the Thirty Years’ War, dominated the period of Grotius’s life. This was a righteous, religious war wherein the only outcome acceptable to the opponents was either the conversion or the annihilation of the opposing side. Even when the Roman Church might have exercised its influence in urging moderation of violence, it did not.

 On the contrary, Church leaders often seemed determined to destroy forever the heresy of the Reformation through the annihilation of its adherents. This was a war fought on behalf of God and, like the Israelites in the wars of the Old Testament; its soldiers were not constrained by any rules whatsoever. In Grotius’s own words, it was the conduct of this war that motivated him to write The Law of War and Peace.

I have had many and weighty reasons for undertaking to write upon this subject. Throughout the Christian world I observed a lack of restraint in relation to war, such as even barbarous races should be ashamed of. I observed that men rush to arms for slight causes, or no cause at all, and that when arms have once been taken up there is no longer any respect for law, divine or human: It is as if, in accordance with a general decree, frenzy had openly let loose for the committing of all crimes.

Grotius’s objective was to supplant the impotent and corrupt ecclesiastical authority with an external, objective, secular author ity that the competing political interests (l.e. nation-states) would accept-a corpus of international laws. In a famous passage he establishes with finality that the domain for his enterprise is all of humankind regardless of race, religion, or national affiliation: “What we have been saying [that natural laws are binding on all mankind would have a degree of validity even…if there is no God, or (if) the affairs of men are of no concern to Him.” Let us now turn to Grotius’s work. Law and Moral Principles

The central theme of The Law of War and Peace is that the relations between states should always be governed by laws and moral principles just as are relations between individuals. This assertion is pivotal because, if true, it restricts both the authority of the Church and that of sovereign states (and their rulers).

Such limitations on secular and Church authority are necessary if international laws are to have any force. But in order for his argument to persuade, Grotius must first show that the moral principles operative in interpersonal relations are at the foundation of municipal (civil) laws. Only then can he stand any chance of convincing us that analogous rules apply (or should apply) in the society of states.

Grotius tackles the first issue by grounding municipal law in a law of nature that is, as he puts it, “unchangeable-even in the sense that it cannot be changed by God.” Our discussion of inter- national law must build, therefore, on the foundations that Grotius lays in his theory of natural law. Let us start by identifying the different types of law that Grotius recognizes and examining how they are related to one another in his system of jurisprudence.

Grotius divides all laws into two broad types: natural law and volitional law. Of the former he says:

Act, according

The law of nature is a dictate of right reason which points out that an in it a quality of moral baseness or moral necessity.

And later:

As it is or is not in conformity with rational nature, has

In discussing the law of nature, the question is this, whether an act can be performed without injustice; and injustice is understood to be that which is utterly repugnant to a rational and social nature.6

When Grotius uses the term natural law, he is referring to phenomena in the realm of interpersonal relationships the same way a scientist explains phenomena concerning inanimate bodies in terms of the laws of physics? He argues that there is something in the nature of humans as rational, social beings that is manifested in human interaction as behavioral patterns.

 When humans objectively apprehend the patterns, they can express them as abstract universal or natural laws. Such laws are as universal and timeless for human beings as are the laws of nature that explain and predict the interaction of inanimate substances. These universal laws are the first principles from which human reason deduces moral truths.

Read: Chap#4 Secularization of the Just War Tradition | Part II

Volitional laws, on the other hand, may be set aside under certain circumstances, such as in wartime; or they may be changed to reflect the particular needs of a people or the times in which they live. Volitional laws may be either human or divine. In either case, they should never be contrary to the laws of nature; and, in fact, volitional laws that decree anything contrary to the laws of nature are invalid.

Human volitional laws can be modified by consent and reflect the times, customs, and necessities of those who consent to them. Volitional laws are best understood as an ever-changing evolving expedient to commodious living. Natural laws, which often provide the principles or foundation upon which volitional laws are conceived, cannot be set aside with the “tide of men’s fortunes.” For example, laws in times of war differ from those in peacetime, even though the same fundamental principles provide the foundations for them all.

Domestic relationships, such as those between a father and his chill Volitional human laws are of three types. One type concerns calls “municipal laws” and “laws of nations.” Both of these are dren or a master and his employees. The remaining types Grotius based on consent, either explicit or implicit, and can be either writ ten or simply customary. We will return to each type of law in more detail in the course of this exegesis.

The fundamental tenet of Grotius’s conception of natural law is that human beings are social creatures-civil society must have existed in the state of nature (even if states did not) because it proceeds from “essential traits implanted in man.” These traits include the disposition to sympathize with others, a disposition to fulfill promises, the ability to know and act in accordance with general principles, the ability to use language, and a proclivity to inflict penalties on individuals in accordance with their just deserts.

Thus, not self-preservation but life in society forms the fundamental basis for natural law. While self-preservation is an instinctive disposition, it is not the most fundamental value as evidenced by man’s (and other social creatures’) willingness to encounter great personal risk to protect families and communities.

This concept is crucial because from it Grotius concludes that neither persons nor states have an absolute right to self-defense. Even if a person was being attacked by a ferocious wild beast, for example, the right of self-defense would not justify his seizing another’s child and tossing it to the attacking animal in order to divert the danger away from him. Thus, the right of self-defense is limited at least to the extent that one cannot impose unreason- able dangers on other innocent persons in order to save oneself.

The type of society that is natural to humans is not one of loose anarchic associations, but a society that consists of ordered communities where individuals may live in concord with their fellows. Furthermore, society is not simply an expedient (as Thomas Hobbes claims). For man’s very nature as a social being would “lead him into the mutual relations of society (even] if he had no lack of anything.”

Because it is in man’s nature that he live in society. “It is a rule of the law of nature to abide by pacts” so that members may oblige themselves to one another, the disposition to live in society and abide by pacts is the source of municipal law that is thereby grounded in the consent of those whom it affects. Grotius summarizes part of the relationship between natural law and municipal law thus:

For the very nature of man, which even if we had no lack of anything would lead us into the mutual relations of society, is the mother of the law of nature. But the mother of municipal law is that obligation which arises from mutual consent; and since this obligation derives its force from the law of nature, [human] nature may be considered, so to say, the great-grandmother of municipal law.

Grotius adds that, while expediency is not the motive behind municipal laws, they are reinforced by it in that expediency pro- vides the “opportunity” for civil government and municipal laws that help cultivate the social life. Thus, man’s rational nature compels him to adopt municipal laws that are an expedient to increased welfare.

Natural laws either obligate, prohibit, or, by forfeit, permit. Most volitional laws concern affairs that are neither obligatory nor prohibited under natural law; that is, they are permitted. Such laws are, however, binding because individuals have given their consent to them, either explicitly or implicitly, and this constitutes having entered a pact with others who are subject to these laws and, of course, “abiding by pacts is a rule of nature.” This formulation successfully grounds obedience to volitional law in moral principles without claiming that the content of particular municipal laws (such as those concerning swimming or fishing above the milldam) have inherent moral significance.

An example will be helpful here Grotius notes that all persons have a natural right to those goods necessary for survival. Natural law does not prohibit owner- ship of additional goods, and volitional law extends the right of ownership to these. “Thus ownership, such as now obtains, was introduced by the will of man; but, once introduced, the law of nature points out that it is wrong for me, against your will, to take away that which is subject to your ownership.”

 The law of nature that grants everyone the right to that which is necessary for survival can never be superseded by volitional law, and any law that deprives people of their basic survival needs is invalid because it is contrary to natural law. Ownership of necessities is, therefore, guaranteed by natural law, whereas ownership of additional goods is permitted by natural law (in that it is not forbidden) and legislated by volitional law; and volitional law is itself grounded in natural law through the innate human disposition to abide by pacts.

The significance of this to our enterprise is that it means that no one-not even heads of state such as Muammar Khadaffi, Manuel Noriega, Richard Nixon, or Saddam Hussein-is outside of either natural or volitional laws. Moreover, treaties entered into by leaders on behalf of their nations constitute instances of volitional laws and cannot be abrogated without the consent of all parties. As Grotius puts it resists the authorities resists what God has appointed, and those who resist will incur judgment”. Augustine interprets this to mean that humans must obey even unjust laws for the sake of order:

The people of Christ, whatever be their condition-whether they be kings, princes, judges, soldiers, or provincials, rich or poor, bond or free, male or female-are enjoined to endure this earthly republic. wicked and dissolute as it is.

Aquinas defends the second perspective. He argues that one’s individual conscience must always be the final arbiter of moral choices. He grounds his position in an understanding of human nature quite different from Augustine’s. Augustine believes that humans are naturally disposed to sin; hence, the very purpose of political authority is to impose an imperfect peace on stained beings. Aquinas, on the other hand, sees in people’s rational and social nature a disposition to beneficence:”

The first precept of [natural] law [is] that good is to be done and ensued and evil is to be avoided.” The purpose of civil authority is to foster “the unity and peace of the people,” and when a duly constituted authority fails to accomplish this, it may be deposed. “Man is bound to obey secular princes insofar as this is required by the order of justice. Wherefore if the prince’s authority is not just but usurped, or if he commands what is unjust, his subjects are not bound to obey him.”

Aquinas is not questioning the divine authority of civil government, but he locates it in the office rather than the individual who fills the office; and because all human beings are fallible, a ruler’s commands can never be absolutely binding on his subjects.

The premises of the two thinkers contradict each other: Augustine holds that revelation is the source of moral truth; Aquinas contends that humans can discover moral truths through reason. In the former case, the last word concerning right and wrong conduct comes “from the top”-from God through either papal authority or the state-while in the latter view the last word comes from humans using their reason.

Augustine generally equates morality with legality: Aquinas sees moral truths as the foundation of positive laws.  Grotius’s position on this topic initially seems to favor the Augustinian perspective, but further analyze sis shows that it fuses together the two views.

Grotius certainly denies to citizens the right to resist a tyrannical ruler and includes among his list of unjust wars those waged by an oppressed people to gain freedom. This seems paradoxical when contrasted with the progressive character of his work as a whole-enough so that one classic writer on international law attributes this apparent inconsistency to the needs of the times in which Grotius wrote.

What is the explanation of these views, so foreign to the spirit of his teaching and his personal condition?…his frowning upon rebellion and the favoring of authority were in accordance with what were considered to be the essential needs of the times…. At a time of general uncertainty and of loosening of traditional ties of society, national and international, order was looked upon as the paramount dictate of reason…. Considerations of this order must have weighed heavily with one in whose work the desire for peace was the dominant motive and ever-recurring theme.

Like: Chap#4 Secularization of the Just War Tradition | Part I


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