Skip to Content

Lecture Text & Audio:
Dr. Thomas Osborne on Francisco de Vitoria and the Law of Nations


“Francisco de Vitoria on the Law of Nations and the Natural Partnership of Different Peoples”


by Dr. Thomas Osborne
Professor of Philosophy
University of St. Thomas, Houston
September 22, 2017
Part of the 2017-18 St. Vincent de Paul Lecture and Concert Series, endowed by Barbara and Paul Henkels


Recent political events in both Europe and North America have brought to the forefront issues surrounding free trade and immigration. Globalism, which was once seen as a means or even goal of social and political progress, has fallen under suspicion. The failure of Western powers to establish a stable peace in the Middle East has led to widespread doubt about not only the possibility but also the legitimacy of military intervention in the internal affairs of sovereign states such as Syria. Although economic and technological developments have shaped these current difficulties, there are underlying conceptual problems which precede them. For instance, what counts as a sovereign state? Does an international organization such as the United Nations or the European Union have the right to punish sovereign states and to protect its citizens from tyranny? To what extent is an individual state able to intervene in a dispute between two other states? Would it ever have an obligation to do so? I will argue that Francisco de Vitoria’s (d. 1546) account of the law of nations (ius gentium) in the context of the natural partnership of peoples sheds light on some of these problems, even if he does not give us complete answers, and even though answers to such conceptual problems usually do not directly entail any particular policies or political decisions.

Vitoria was the Dominican originator of the sixteenth-century Thomist revival in Spain at the University of Salamanca, and held that the theologian had a responsibility to address a wide range of issues, among which we would include political and legal philosophy. For our purposes his most relevant lectures include a set on the Spanish Conquest of the Americas, called On the American Indians (Relectio De Indis) and another more general set called On the Law of War (Relectio De Iure Belli). Vitoria’s concern for the proper treatment of the Native Americans and in general for the rule-governed nature of international relations led James Brown Scott to call him “the founder of the modern law of nations.”[1] Marcelo Sanchez-Sorondo writes, “he proposes for the first time international law in modern terms, parting from the requirements of the social, cultural, and religious plurality of states.”[2] Despite these assessments, other scholars have pointed out that Vitoria lacked some essential elements of contemporary international law.[3] For example, in his time there were no international courts or tribunals. Whatever the relevance of Vitoria for international law, his work brings together a host of issues concerning the nature of sovereignty and the roles of borders, and in particular the way in which different sovereign states form part of one wider human community. This wider community is governed by a law or right of nations, which binds different rulers and states, and can be enforced by individual states. This law of nations governs such actions as the reception of ambassadors, free passage, trade, and war.

It will be helpful to first look at what this law of nations is in relation to other kinds of law, such as the natural law and the civil law of individual states. It will then be helpful to consider the law of nations in light of authority. What would it mean to have a law if there is no mechanism for enforcing the law? Then we can consider the content of the law of nations, and how it is based on natural reason. We will see how Vitoria’s account of the law of nations was favorable to trade and immigration, although later scholastics criticized him on precisely these points.

What kind of law could govern the behavior of those who belong to different political communities? In his Summa Theologiae, Thomas describes five kinds of law, namely the eternal law, natural law, human law, divine law, and the law of sin.[4] The eternal law is God’s ordering of the universe. The natural law is a human participation in this ordering. Unlike other creatures that tend towards their end unknowingly, humans can deliberate about how to achieve their own good and the common good. This natural law governs all humans, but it is general and by itself has no obvious sanctions. It tells us not to kill or steal, but it does not directly apply to many difficult cases or determine precisely what a punishment should be. It is promulgated in the human heart rather than by a human authority in a written or oral code. Human law derives from and determines the natural law. It corresponds most clearly to our ordinary notion of law, and includes the civil law and perhaps even canon law. It determines crimes and punishments, and directs human action towards the common good. Divine law was once the Mosaic Law and is now the New Law that is written in the hearts of Christians. The law of sin is less clearly a law, since it describes the sensuality that inclines humans away from reason.

Two Latin words are sometimes used to indicate “law”, namely “lex” and “ius.” [5] The first only refers to law. “Ius” according to Thomists generally indicates an objective right, or something that is due to another, although among later Thomists it can also mean a subjective right or power. Sometimes “ius” also indicates a kind of law, as when natural law or natural right (ius naturale) is contrasted with the law or right of nations (ius gentium). Roman jurists and the Christian tradition had included the law of nations (ius gentium) as a kind of law distinct from both the natural law and the civil law. According to Justinian’s Institutes:

The law of nations (ius gentium) and the civil law (ius civile) are distinguished as follows. All peoples with laws and customs apply law which is partly theirs alone and partly shared by all mankind. The law which each people makes for itself is proper to its own political community (civitas) . . . But the law which national reason makes for all mankind is applied the same everywhere. It is called “the law of nations” because it is common to every nation.[6]

Individual nations make their own laws. The law of nations includes either that which is common to every nation and to at least some extent can govern interaction between nations.

In order to understand how the law of nations can be a true law, it is helpful to consider the four elements that make up the definition of law. According to Thomas, law is “a certain ordinance of reason for the common good, by the one who has the care of the community, and promulgated.”[7] The first element of this definition, that it is an ordinance of reason, distinguishes Thomas’s theory from other theories that would emphasize the binding power of the lawgiver’s will. The end of the law, which is the common good, distinguishes it from an unjust command, and draws our attention to the nature of the community in which it is based and to which it is directed. The third element of the definition emphasizes that it must be made by someone who has authority. The fourth and last element indicates that this authority must make the law known to those who are bound by it.

Human law can be made only by someone with legitimate political authority. Private individuals can suggest or direct action, but they cannot legislate. According to Thomas and Aristotle, although the head of the family has authority over its members, he lacks the authority to pass laws.[8] The family is an incomplete or imperfect natural community that depends on and is directed to the complete or perfect political community.[9] What counts as such a perfect political community? Aristotle emphasizes self-sufficiency and clearly has in mind the Greek city-state that ceased to exist during the Hellenistic period. Thomas himself was aware of various kind of political organization and levels of authority, such as the Holy Roman Empire, Kingdoms, and relatively autonomous cities. Vitoria himself lived in the somewhat recently united Kingdom of Spain. What kind of political unit has the authority to pass laws?

According to Vitoria, a relevantly complete community “is one whole per se, in which is not part of another commonwealth, but has its own laws, its own independent policy (concilium), and its own magistrates, such as is the Kingdom of Castile and Aragon, and other similar ones.”[10] This description might seem straightforward, but in his time and ours the criteria can be vague. For instance, in the just cited passage Vitoria mentions the Kingdom of Castile and Aragon as a complete kingdom. Nevertheless, he also notes that the Duke of Alba and the Count of Benavente are parts of this kingdom and yet have the authority that a complete community has, such as that of making war. Moreover, Vitoria recognizes that cities such as Milan are subject to the Holy Roman Empire.[11] Nevertheless, Milan itself is a perfect or complete community. Consequently, the Duke of Milan can declare war on his own without the Emperor. Vitoria states that in these unclear cases custom indicates the difference between a complete and an incomplete community. But the original criteria that he gives seem to be based not so much on custom but on the structure and properties of the relevant regimes.

Despite the potential difficulties in determining the scope and authority for civil law, there are graver difficulties with respect to that law which governs behavior between political communities. Each complete political community has its own human laws that direct the actions of its members to the common good of such a community. What common good would the law of nations be directed to? What would count as an authority that could make the law of nations? How would such a law be promulgated?

Thomas’s thought on the “law of nations” (ius gentium) is sketchy and does not clearly account for the relationship between states.[12] He also does not seem entirely consistent about the relationship between the law of nations, positive law, and natural law. In his discussion of the law of nations in the Prima Secundae of the Summa Theologiae, Thomas indicates that this law is a kind of human positive law that is distinct from the civil law.[13] The law of nations is derived from the natural law as conclusions are derived from principles. For instance, the law of nations governs buying and selling. The civil law determines the natural law by specifying crimes, punishments, etc. Whereas in this text Thomas states that the law of nations is a kind of human law, he identifies it as part of the natural law later in the Secunda Secundae of the Summa Theologiae and in his Commentary on the Nicomachean Ethics. In these two later texts, Thomas states that the law of nations is natural even though sometimes it is divided from natural right.[14] He distinguishes the jurists’ usage from that of Aristotle. The jurists use “natural right” to describe laws that follow inclinations that are common to humans and other animals. For example, laws that involve the joining of men and women and the education of children belong to natural right. In contrast, the jurists call the “right of nations” that which governs humans insofar as they are rational. By the law of nations agreements must be observed and legates kept safe. Thomas notes that both are “natural” in Aristotle’s usage, since they rest on natural inclination and not on positive law. Consequently, although in this context Thomas mentions the relationship between nations, he does not in this context develop an account of how the relevant rules could be develop or changed, or in what way they might be enforced.

Unlike Thomas, Vitoria consistently describes the law of nations as including positive law. In his Commentary on the account of the law of nations in the Secundae Secundae of Thomas’s Summa Theologiae, Vitoria similarly emphasizes that the disagreement about whether the law of nations belongs to natural or positive law is primarily verbal, but he describes this verbal difference in a slightly different way.[15] Like Thomas, Vitoria notes that jurists describe precepts to worship God or honor parents as belonging to the law of nations and not the natural law. They restrict the natural law to what humans share with other animals. But unlike Thomas, Vitoria contrasts the jurists not with Aristotle but with theologians. According to the theologians, these precepts that follow rational nature, such as those that command the honoring of parents and the worship of God, are part of the natural law. Theologians restrict the law of nations to other precepts that do not immediately follow from natural law. Consequently, the jurists use the term “law of nations” to cover a broad set of natural law precepts, whereas the theologians use the term more properly and in a better way to describe a kind of positive law. It is important that Vitoria recognizes both usages. He is not simply confused about them.[16]

In this same context, Vitoria states that just as in the case of positive law, the law of nations can include what results from either private or public agreements.[17] The public agreements include what is consented to by all nations in order to protect natural law. For instance, the safety of ambassadors is necessary for nations in order to avoid war. Such laws do not follow necessarily from precepts of natural law, since in that case they would simply belong to the natural law. Whereas what is naturally due involves a strict equality, what is due according to the law of nations involves some sort of looser equality based on agreement or consent. Nevertheless, the precepts of the law of nations are necessary insofar as natural right cannot be upheld without them.

Consequently, in Vitoria’s account we can distinguish in different ways between the natural law and the law of nations. According to the jurists, the law of nations is simply that part of the natural law that belongs to what is specifically human, such as the ability to worship God or honor one’s parents. According to the theologians, such precepts belong to the natural law. The law of nations is distinguished from the natural law insofar as it involves a notion of the due that is not determined by nature but in some way by consent. This consent can be indicated by custom. The law of nations is necessary for the following of the natural law.

Despite the variation in usage, Vitoria seems to think of the law of nations primarily in the context of laws that govern different political communities and their rules. It is not based simply on an agreement between different perfect political communities. The law of nations governs all of the complete or perfect communities together insofar as they are part of the whole world. It directs humans to the common good of mankind. Vitoria writes:

[T]he law of nations does not have the force merely of pacts or agreements between men, but has the validity of a positive enactment (lex). The whole world, which is in a sense a commonwealth, has the power to enact laws which are just and convenient to all men; and these are in the law of nations (ius gentium). From this it follows that those who break the law of nations, whether in peace or in war, are sinning mortally, at any rate in the case of the graver transgressions such as violating the immunity of ambassadors. No kingdom may choose to ignore the law of nations, because it has the sanction of the whole world.[18]

According to this account, the law of nations falls under Thomas’s four-part definition of law. But the details are unclear. In particular, Vitoria does not describe how the whole world is able to enact laws or even to enforce them.

In contrast with some extreme proponents of the temporal power of the papacy and the universal authority of the Holy Roman Emperor, Vitoria follows the mainstream Thomist tradition in holding that there is no temporal authority over the whole world.[19] The Holy Roman Emperor’s powers are limited to the Empire itself. Vitoria uses St. Thomas to argue that no political authority has such universal dominion. Although political communities are natural, particular political units are the result not of natural but of human law. With respect to the Pope, Vitoria admits that he has universal spiritual authority and some temporal authority, but denies that papal temporal authority extends beyond the Papal States and some extraordinary situations. Vitoria compares the Pope with the Emperor when arguing that the pope lacks universal political authority: “the proof of this is really quite simple, as it was in the case of the emperor above: because the pope cannot have any dominion except by natural, divine, or human law.” [20] But none of these laws grants the pope temporal authority over the whole world. According to Vitoria, political authority not only produces law, but it also rests on a particular form of human law. There is no plausible legal claimant to worldwide dominion.

If no ruler has authority over the whole world, then how can international disputes or injuries be settled or punished? Vitoria explains that a ruler of a political community has in certain contexts authority over foreigners who would not normally fall under his rule.[21] Vitoria understands a just war in this context. If there is an unjust injury or a sufficiently grave violation of the law of nations, only a legitimate authority can avenge the injury. This same authority can be both part of the dispute and a judge of the dispute. In cases within political communities there is someone above the disputants to whom they must appeal. But between political communities there is no such higher authority, so some civil authority must step in.

Not every act of injustice legitimizes such interference.[22] Whereas some Spaniards had used the sins of the Native Americans to justify the Spanish conquest, Vitoria holds that the same arguments could be used to justify the conquest of Christians, since Christians themselves are also guilty of sodomy, fornication, and robbery. Every political community contains a fair amount of sin. Military intervention is justified only by grave evils, and could be on account of “the personal tyranny of the barbarians’ masters towards their subjects, or because of their tyrannical and oppressive laws against the innocent, such as human sacrifice practiced on innocent men or the killing of condemned criminals to provide food for cannibalism.”[23] Vitoria does not argue that the practice of the Native Americans in fact justifies conquest, but he states that it might make it legitimate. Vitoria’s point is that anyone with political authority and ability can defend the innocent. Such a ruler does not need to appeal to the Pope or some international authority.

The ruler who intervenes in such instances acts not only as a protector but also as a judge. By the law of nations and even by natural law he can inflict penalties on the tyrant. Vitoria writes:

The prince has the authority not only over his own people but also over foreigners to force them to abstain from harming others; this is his right by the law of nations and the authority of the whole world. Indeed, it seems he has this right by natural law: the world could not exist unless some men had the power and authority to deter the wicked by force from doing harm to the good and the innocent. Yet those things which are necessary for the governance and conservation of the world belong to the natural law.[24]

Vitoria’s argument for this point draws on the same argument that Thomas gives to justify the use of deadly force by the political community. According to Thomas, the ruler of the political community, unlike a private citizen, has the authority to command the death of the guilty in order to achieve and protect the common good.[25] The same political authority has the ability to harm both internal enemies by punishing criminals and external enemies through just wars. Vitoria surpasses Thomas by noting that there is a similar need for protection from those who threaten the entire world.

Vitoria’s argument can only be understood if we keep in mind the distinction between self-defense and punishment.[26] A private person or group of persons can defend themselves from enemies, but they cannot punish their enemies. Once the threat has vanished, they cannot as private citizens exact vengeance. Only public authorities should punish them. Similarly, if political communities were related to each other merely as private individuals, then they would not be able to punish aggressors. Leaders would be obliged to cease their hostilities once the threat has ceased. But Vitoria notes that both the Maccabees in the Bible and Christian kings punish those who have been unjust. This ability to punish implies that they have an authority over the unjust foreigners that is similar to the authority that they normally have over their own citizens.

Vitoria emphasizes that this authority to wage war should be exercised sparingly.[27] First, the ruler has less authority over foreigners than he has over his own citizens. Second, the effects of war are so terrible that they will be disproportionate to most offenses. It is better to let most offenses go unpunished. Nevertheless, given a sufficiently grave offense, rulers have the authority to act as judges in their own case. Their authority is based on the need for someone to punish rulers who act unjustly. This need indicates that the prince has authority over foreigners in the same way that the need to punish internal enemies indicates that the ruler of the political community has authority over his own citizens.

What authority makes and promulgates the law of nations? Vitoria thinks that the relevant laws are reasonable and have consent in the whole world, but he is unclear on what this consent could be. They are not mere deductions from natural law in the way that in certain passages Thomas says that the law of nations is. According to Vitoria, even though part of the law of nations remains the same over time, there are additions. The consistency and the development of these new laws seem to rest on their necessity and reasonableness.

The typical example of a right that belongs to the law of nations is the immunity of ambassadors, which is recognized or should be recognized by all nations and has been so recognized from early times.[28] The communication and cooperation between different political communities would be severely impaired if ambassadors could be harmed. This immunity cannot be based on the law of any one political community, because it must be recognized by the communities that interact. Consequently, there is a widely recognized right of ambassadors that is based on an enforceable law that exists apart from any one political system.

As previously mentioned, custom indicates a consent that establishes a precept as part of the law of nations. Vitoria in his On the Law of War mentions several cases in which the law of nations has developed so as to limit what might be done strictly according to natural law. For instance, by the natural law enemy combatants who surrender can be punished by death, since they have unjustly and gravely harmed the political community. Surrendering does not take away their guilt. But Vitoria remarks, “But as many practices in war are based on the law of nations, it appears to be established by custom that prisoners taken after a victory, when the danger is past, should not be killed unless they turn out to be deserters.”[29] The law of nations is indicated here not by deduction from the principles of natural law but by considering actual practice. Brian Tierney thinks that such texts conflict with those passages in which Vitoria states that the law of nations is established by consent.[30] But it seems to me that Vitoria accepts the medieval and Roman view that longstanding custom presupposes some form of consent.[31] The very existence of such a practice indicates that the different nations have consented to this law.

Sometimes a mitigating element of the law of nations applies only to some political communities. For instance, in wars with the Saracens, innocent non-combatants can be enslaved and plundered, since enough compensation can never be taken to satisfy the injuries that have been received from the Saracens.[32] But according to the law of nations Christians cannot enslave other Christians.[33] Although the difference between Christians and Saracens seems primarily religious, Vitoria’s reasoning is not based on religion but on the nature of the war between them. Wars between Christians are temporary and limited in the harm that they do. In contrast, the Saracens are permanently at war with Christian nations. So the damages that can be claimed from the Saracens are greater than those that can be claimed from Christian nations.

In other cases the law of nations makes licit an act that would otherwise be considered unjust under the natural law. For instance, since the purpose of war is to avenge an injustice, by the natural law the victor has the right to take goods only in reparation for injuries and to pay the cost of the war. However, Vitoria writes, “At least in the law of nations, all movable goods become the property of the captors, even if their value exceeds that of compensation of losses.”[34] The victors can take movable goods such as money and material goods even in addition to what they are owed, but they must not take towns or forts. This aspect of the law of nations is not rooted in any reasoning about the natural law. Vitoria shows that it comes from Roman law, canon law, and later Christian practice. Again, the law of nations is not determined by an international decision-making body but rather by the practice and laws of different nations.

Perhaps Vitoria’s most controversial use of the law of nations is in his On the American Indians, in which he argues that the natural partnership and communication of peoples might justify the Spanish conquest of the Americans.[35] Vitoria to some extent bases his argument on aspects of the law of nations that were already recognized in Roman law. However, he also invokes the common scholastic view that all goods were common before the Fall and the subsequent division of mankind into different political units. This natural community of mankind makes hospitality to strangers one of the most important duties of the law of nations. The right to travel (ius peregrinandi) is related, and must be applied impartially to members of different nations. Vitoria writes, “it would not be lawful for the French to prohibit Spaniards from travelling or even living in France, or vice versa, so long as it caused no sort of harm to themselves; therefore it is not lawful to banish visitors who are innocent of any crime.”[36] Injuries against travelers are considered to be injuries against the travelers’ own countries, and consequently a just cause for war on behalf of the injured counties.

Vitoria mentions several related parts of the law of nations that are recognized either in Roman law or follow from natural law.[37] First, Roman law recognized that ships from different countries could put into any port. Second, the natural partnership of peoples entails a right to trade for mutual benefit.[38] Third, goods held in common, such as gold in the earth or pearls in the ocean, are equally available to members of the political community and to those from outside.[39] They are owned by those who find them, even if they are foreigners. Fourth, since every human by nature is a political animal, he has the right to join other political communities, and his children have a right to citizenship if born there. Otherwise such children would not have any nation. According to Vitoria, the Native Americans injured the Spaniards on each of these accounts, and consequently may have thereby justified the Spanish conquest.

Vitoria’s enumeration of these aspects of natural partnership indicates the way in which human beings are not only essentially political, but also part of a community that includes the whole human race. Vitoria generally qualifies the obligations to partnership with phrases such as that in the quote above, namely “so long as it caused no sort of harm to themselves.” Vitoria’s text greatly influenced Hugo Grotius’s (1583-1645) own defense of the rights of travel, trade, and access to the seas.[40] Nevertheless, Vitoria’s arguments did not establish or indicate that these rights are unlimited. Scholars have often pointed out that later writers criticize Vitoria’s understanding of the right to travel and commerce, but these scholars are unclear about whether the criticism is directed against Vitoria’s understanding of what the law of nations in fact holds, or whether there is a criticism of Vitoria’s application of the law of nations to a particular case. Vitoria’s successors seem to criticize him on both counts.

Vitoria’s fellow Dominican Melchor Cano (1509-1560) accepts that there is a right to travel, but he directly criticizes the Spanish claim that the Native Americans violated this right.[41] Cano simply remarks that if the Spanish could be described as travelers, then so could Alexander the Great in his conquest! The disagreement between Cano and Vitoria on this point is not over the right to travel but over its application to the New World. Similarly, the Jesuit Francisco Suarez (1587-1617) writes that one cause of war is if another prince “denies the common right of nations without reasonable cause, as the transit of travelers, common commerce, etc.”[42] Like Vitoria, he thinks that a violation of the right to travel can be a just cause of war. But this right to travel is limited by the needs of the political community. For instance, in his discussion of faith, Suarez states that Christian rulers can for a just reason prevent unbelievers from living in or traveling in Christian lands.[43] The Christian rulers can limit their right to travel and live only to protect their own political community. Suarez and Vitoria do not disagree at least in general over whether limitations of trade and travel can be a just cause for war. The practical problem that they do not discuss is when such limitation would be reasonable and consequently not an injury or cause for war.

The Dominican Domingo de Soto (1495-1560) like Vitoria defends the right to travel to an unusual extent. In a work on almsgiving Soto defends at length the rights of beggars to travel and beg across borders, assuming that no injury is done.[44] On the other hand, Soto directly criticizes Vitoria’s account of the right of foreigners to goods that are held in common. Soto appeals to the recognized practice that the local community has dominion over them.[45] It would be illicit for the French to take natural goods such as gold from Spain, just as it would be for the Spanish to take them from the French. Taking goods in this way is theft. Soto does not deny that the law of nations governs the relations with respect to these goods. The disagreement with Vitoria is not merely over the application of the law of nations but over its content. The Jesuit Luis de Molina (1535-1600) similarly criticizes Vitoria’s appeal to the actual practice of different nations.[46] Whereas Vitoria used Roman law to argue that waterways and natural goods in the earth are common, Molina argues that everyone recognizes that they belong to a political community. He notes that the King of Spain and Portugal to prohibit foreigners to fish for sea-carp near their shores, and in general notes that Vitoria’s account conflicts with the practice of various countries. On Vitoria’s view, fish would seem to be common, and the political authorities would lack the ability to regulate fishing. Both Soto and Molina against Vitoria that even common natural goods belong to the political communities that govern them. They criticize not only Vitoria’s account of what the law of nations contains.

Whether or not Vitoria is justly described as the “father of international law,” his academic position and political situation make it possible for him to develop more carefully than his predecessors an account of the way in which different political communities and their rulers are bound by the law of nations. It seems to me that his conceptual framework can be applied to our current context, in which there are a variety of different sovereign states and communities such as the European Union which also claim sovereignty. To a large extent the relations between these different communities must be governed by common practice and custom, and ultimately rooted in recognition of a worldwide community of human beings. But there is no one institution, not even the United Nations, which can claim the authority by itself to create binding laws or judge between nations. Sovereign states may agree to submit themselves to a kind of arbitration or agreement. But otherwise the ruler of a sovereign state must be both the prosecutor and judge for disputes between political communities. It is dangerous for belligerents themselves to have public authority. But in both Vitoria’s day and in ours there is no other option, and the world community needs rulers to punish injuries in order for humankind to flourish.

Although it seems to me that Vitoria’s conceptual framework remains valid, it does not seem to me that it gives many concrete answers for today’s problems concerning immigration and globalization. He does remind us that humans share a common nature and good, and that there is a natural partnership among peoples in achieving their common good. These considerations by themselves are in favor of freer immigration policies and trade. Nevertheless, Vitoria also recognizes that political rulers may limit travel and trade if there is a serious reason to do so, and other writers pointed out that Vitoria overlooks the common custom of nations in limiting access to goods such as precious metals and fish. Moreover, on Vitoria’s own account, the law of nations develops over time. Consequently, present policy debates should take into account current practices and international agreements as well as economic, political, and cultural effects. Reading Vitoria does not give us any policy prescriptions, but it does provide us with a conceptual framework with which to think of different sovereign states as participating in a wider community that is governed by law. According to Vitoria, this community is based on the shared humanity of not only Spaniards and Frenchman, but even Saracens and the Native Americans of the New World.


[1] James Brown Scott, The Catholic Conception of International Law (Washington, D.C.: Georgetown University Press, 1934), vii.

[2] Marcelo Sanchez-Sorondo, “Vitoria: The Original Philosopher of Rights,” in Kevin White, ed., Hispanic Philosophy in the Age of Discovery (Washington, D.C.: The Catholic University of America Press, 1997), pp. 69-68, at 66.

[3] Bernice Hamilton, Political Thought in Sixteenth-Century Spain: A Study of the Political Ideals of Vitoria, De Soto, Suarez, and Molina (Oxford: Clarendon, 1963), 98; Brian Tierney, “Vitoria and Suarez on Ius Gentium, Natural Law, and Custom,” in Amanda Perreau-Sauusine and James Bernard Murphy eds., The Nature of Customary Law (Cambridge: Cambridge University Press, 2007), 101-124, at 114. 

[4] Thomas, Summa Theologiae, I, q. 96.

[5] For the use and development of these terms in Thomas and the Thomistic tradition, see especially Annabel S. Brett, Liberty, Right, and Nature: Individual Rights in Later Scholastic Thought (Cambridge: Cambridge University Press, 1997), 88-164, and more substantially Sanitago Ramirez, El Derecho de Gentes: Examen Critico de la Filosofia del Derecho de Gentes desde Aristoteles Hasta Francisoc Suarez (Madrid/Buenos Aires: Ediciones Studium, 1955).  For a critical review of some literature on such rights in Spanish scholasticism, see Brian Tierney, “Aristotle and the American Indians – Again,” Christianesimo nella storia 12 (1991): 296-322, at 297-305. 

[6] “Ius autem civile vel gentium ita dividitur: omnes populi, qui legibus et moribus reguntur, partim suo proprio, partim communi omnium hominum iure utuntur: nam quod quisque populus ipse sibi ius consitutit, id ipsius proprium civitatis est . . . quod vero naturalis ratio inter omnes homines constituit, id apud omnes poulos peraeque custoditur vocatur ius gentium, quasi ure omnes gentes utantur.”  Institutes, 1.2.1, in Paul Krueger, ed., Justinian’s Institutes, trans. Peter Birks and Grant McCleod (Ithaca, NY: Cornell University Press, 1987), 36.  I have slightly modified the translation on 37.  For the context, see Geoffrey MacCormack, “Sources,” in Ernest Metzger, ed., A Companion to Justinian’s Institutes (Ithaca, NY: Cornell University Press,” 1-17, at 4-5.

[7] “quadeam rationis ordination ad bonum commune, ab eo qui curam communitatis habet, promulgata.”   Thomas, S.T., I-II, q. 90, art. 4.

[8] Thomas, S.T., I-II, q. 90, art. 3, ad 3.

[9] Vitoria, In I-II, q. 90, art. 3 (trans. Pagden/Lawrance, 158; ed. Herdedia, vol. 6, 414); On Civil Power, q. 3, art. 7, n. 24 (trans. Pagden/Lawrance, 43-44; ed. Urdanoz, 193-195).  See Luis Valenzuela-Vermehren, “The Origin and Nature of the State in Francisco de Vitoria’s Moral Philosophy,” Ideas y Valores 62 (2013): 81-103, at 97-101.

[10] “est per se unum totum, in qua non est alterius reipblicae pars, sed quae habet proprias leges, proprium concilium, et proprios magistratus, quae est regum Castellae et Aragoniae et alii similes.”  Vitoria, On the Law of War, q. 1, art. 2, n. 3 (trans. Pagden/Lawrance, 301; ed. CHDP vol. 6, 118).  I have altered the translation.  See also On the American Indians, q. 1, art. 6  (I.1.15) (trans. Pagden/Lawrance, 250; ed. CHDP, vol. 5, 29-30).  On this basis it seems too strong to say with Georg Cavallar that “Vitoria had no clear conception of state sovereignty,” in his The Rights of Strangers: Theories of International Hospitality, the Global Community, and Political Justice since Vitoria (Aldershot/Burlington, VT: Ashgate, 2002), 105.

[11] Vitoria, In II-II, q. 40, art. 1, n. 4 (ed. Heredia, vol. 2, 281).

[12] Victor Salas, “Francisco de Vitoria on the Ius Gentium and the American Indios,” Ave Maria Law Review 10 (2012): 331-341, at 333-335; Paula Oliveira e Silva, “The Concept of ius gentium: Some Aspects of Its Doctrinal Development from the ‘School of Salamanca’ to the Universities of Coimbra and Evora,” in Kirstin Bunge, et al., eds., The Concept of Law (lex) in the Moral and Political Thought of the ‘School of Salamanca (Leiden/Boston: Brill, 2016), 106-125, at 106-112.

[13] I-II, q. 95, art. 4.

[14] Thomas, Sententia Ethicorum, lib. 5, lect. 12; S.T., II-II, q. 47, art 3.

[15] Vitoria, In II-II, q. 57, art. 3, n. 2 (ed. Heredia, vol. 3, 13)

[16] Tierney, “Vitoria and Suarez,” 114, attributes the variation in usage to the particular context of the work.  See also Ramirez, El Derecho de Gentes, 136-145.

[17] Vitoria, In II-II, q. 57, art. 3, nn. 2-3 (ed. Heredia, vol. 3, 13-15)

[18] “Quod ius gentium non solum habet vim ex pacto et condicto inter homines, sed etiam habet vim legis.  Habet enim totus orbis, qui aliquot modo est una respublica, potestatem ferendi leges aequas et convenientes omnibus, quales sunt in iure gentium.  Ex quo patet quod mortaliter peccant violantes iura gentium, sive in pace sive in bello. In rebus tamen gravioribus, u test de incolumitate legatorum, neque licet uni regno nolle teneri iure gentium: est enim latum totius orbis auctoritate.”  Vitoria, On Civil Power, q. 3, art. 4, n. 21  (trans. Pagden/Lawrance, 40; ed. Urdanoz, 192-193).  Translation modified.

[19] Vitoria, On the American Indians, q. 2, art. 1 (I.2.1) (trans. Pagden/Lawrance, 252-258; ed. CHDP, vol. 5, 33-42).

[20] “Et satis est probatum, sicut supra de Imperatore, quia non potest ei convenire dominium, nec iure naturali nec divino nec humano.”   Vitoria, On the American Indians, q. 2, art. 2 (I.2.4) (trans. Pagden/Lawrance, 260); ed. CDHP, vol. 5, 47.

[21] Vitoria, On the Law of War, q. 1, art. 4 (IV.1.1-6) (trans. Pagden/Lawrance, 304-306; ed. CHDP, vol. 6, 130-140); On the American Indians, q. 3, art. 1, n. 8 (I.3.7) (trans. Pagden/Lawrance, 283; ed. CDHP, vol. 5, 86).  For a discussion of this view in light of later law over municipal sanctions, see Scott, Catholic Conception of International Law, 59-125).

[22] Vitoria, On the Law of War, q. 1, art. 3 (III.4.5) (trans. Pagden/Lawrance, 304; ed. CHDP, vol. 6, 128); On the American Indians, q. 2, art. 5, n. 40 (trans. Pagden/Lawrance, p. 274).

[23] “posset esse propter tyrannidem vel ipsorum dominorum apud barbaros vel etiam propter leges tyrannicas in iniuriam innocentium, puta quia sacrificant homines innocents vel alias occidunt indemnatos ad vescendum carnibus eorum.” (I.3.14)  Vitoria, On the American Indians, q. 3, art. 5 (trans. Pagden/Lawrance, pp. 287-288; ed. CHDP, vol. 5, 93).  Translation slightly modified.

[24] “princeps non tantum habet auctoritatem in suos sed etiam in extraneos, ad coercendum illos ut abstineat ab iniuriis; et hoc iure gentium et orbis totius auctoritate.  Immo videtur quod etiam iure naturali, quia videtur quod aliter obris stare non posset nisi esse paenes aliquos vis et auctoritas deterrendi improbos ne bonis noceant.  Ea autem quae necessaria sunt ad gumernationem et conservationem orbis,, sunt de iure naturali.”  Vitoria, On the Law of War, q. 1, art. 4 (IV.1.5) (trans. Pagden/Lawrance, p. 305; ed. CHDP, vol. 6, 136).

[25] See Thomas, S.T., II-II, q. 40, art. 1; q. 64, art. 3.

[26] Vitoria, On the Law of War, q. 1, art. 1 (I.2) (trans. Pagden/Lawrance, 297-298; ed. CHDP, vol. 6, 104). 

[27] Vitoria, On the Law of War, q. 1, art. 3 (III.5); conclusion (trans. Pagden/Lawrance, 304, 326-327; ed. CHDP, vol. 6, 128, 202-207).

[28] Vitoria, On Civil Power, q. 3, art. 4, n. 21 (trans. Pagden/Lawrance, 40; ed. Urdanoz, 191); On the American Indians, q. 3, art. 1 (I.3.7)  (trans. Pagden/Lawrance, 283; ed CHDP, vol. 5, 86).

[29] “Sed quia in bello multa iure gentium constituta sunt, videtur receptum consuetudine ut captivi, habita Victoria et periculo transeunte, non interficianture nisi forte sint profugae.”  Vitoria, On the Law of War, q. 3, art. 6 (IV.2.6) (trans. Pagden/Lawrance, 321; ed. CHDP, vol. 6, 184).

[30] Tierney, “Vitoria and Suarez,” 110-114.

[31] David Ibbetson, “Custom in Medieval Law,” in The Nature of Customary Law, 151-175, at 152, 156.

[32] Vitoria, On the Law of War, q. 3, art. 3 (IV.2.3) (trans. Pagden/Lawrance, 318; ed. CHDP, vol. 6, 176) . 

[33] Vitoria states that the custom among Christians is an abrogation of the law of nations in his In II-II, q. 57, art. 4, n. 5 (ed. Heredia, vol. 3, 17).

[34] “Mobilia quidem iure gentium omnia fiunt occupantium, etiam si excedant compenationem damnorum.”  Vitoria, On the Law of War, q. 3, art. 7 (IV.2.7) (trans. Pagden/Lawrance, 322; ed. CHDP, vol. 6, 186).

[35] Vitoria, On the American Indians, q. 3, art. 1 (I.3.1) (trans. Pagden/Lawrance, 278-284; ed. CHDP, vol. 5, 76-87).  For summaries, see Cavallar, Rights of Strangers, 107-112);  Anthony Pagden, “Dispossessing the Barbarian,” in Anthony Pagden, Spanish Imperialism and the Political Imagination: Studies in European and Spanish American Social and Political Theory 1513-1830 (New Haven, CT: Yale University Press, 1990), 13-36, at 21-22; Scott, Catholic Conception of International Law, 16-27

[36] “Quarto, non liceret gallis prohibere hispanos a perigratione Galliae [vel etiam habitatione, aut e contrario, si nullo modo cederet in damnum illorum, immo facerent iniuriam].  Ergo nec barbaris.” Vitoria, On the American Indians, q. 3, art. 1 (I.3.1) (trans. Pagden/Lawrance, 278; ed. CHDP, vol. 5, 78).

[37] Vitoria, On the American Indians, q. 3, art. 1 (I.3.3-5) (trans. Pagden/Lawrance, 279-281; ed. CHDP, vol. 5, 81-85).  For some relevant passages, see Institutes 2.1 (ed. Krueger, 54-60).

[38] For international trade in Spanish scholasticism, see Alejandro A. Chafuen, Faith and Liberty: The Economic Thought of the Late Scholastics (Lanham, MD: Lexington, 2003), 74-77.

[39] For subsurface property, see Chafuen, Faith and Liberty, 38-40.

[40] Cavallar, Rights of Strangers, 144-155.  Although Cavallar, 147, holds that Grotius’s doctrine of the freedom of the seas was new, it can be found in some way both in Vitoria and in Roman Law.  See Vitoria On The American Indians, q. 3, art. 1 (I.3.2, 4) (trans. Pagden/Lawrance, 279, 281; ed. CHDP, vol. 5, 81, 83); Institutes 2.1.1, 4 (ed. Krueger, 54).

[41] Melchor Cano, De Domino Indorum, in Juan de la Pena et al., eds., De Bello Contra Insulanos Intervencion De Espana En America (Madrid: Consejo Superior de Invesitgaciones Cientificas, 1982), 555-581, at 579.   See Pagden, “Dispossessing the Barbarian,” 23-25; Tierney, “Vitoria and Suarez,” 109.

[42] “si neget communie jura gentium sine rationabili causa, ut transitum viarum, commune commercium, etc.”  Suarez, De Charitate, tract. 3, disp. 14, sect. 4, n. 3 (vol. 12, p. 744).

[43] Suarez, De Fide, tract. 1, disp. 18, sec. 3, n. 9 (vol. 12, p. 447).  See John P. Doyle, “Suarez on Preaching the Gospel to People Like the American Indians,”  in John P. Doyle, Collected Studies on Francisco Suarez, S.J. (1587-1617), ed. Victor M. Salas (Leuven: Leuven University Press, 2010), 257-312, at 300.

[44] Annabel S. Brett, Changes of State: Nature and the Limits of the City in Early Modern Natural Law (Princeton, N.J.: Princeton University Press, 2011), 11-36; Tierney, “Vitoria and Suarez,” 109.

[45] Domingo de Soto, De Justitia et Jure, lib. 5, q. 3 (Salamanca, 1556), p. 423.  See Pagden, “Dispossessing the Barbarian,” 24.

[46] Luis de Molina, De Justitia et Jure, disp. 105, in vol. 1 (Mainz, 1659), p. 428.  See Hamilton, Political Thought, 102-104.



Receive Thomas Aquinas College
lectures and talks via podcast!


Get it on iTunes Available on Stitcher RSS
Dr. Thomas Osborne (2017)
Isabella Hsu (’18) on discussion method

“In our classroom discussions, we are responsible for our own education. We have to get our hands dirty, to figure out the material, to let it become part of us and make us better people. That is real learning.”

– Isabella Hsu (’18)

Redondo Beach, California

“I am grateful to Thomas Aquinas College for educating new leaders for our Church, leaders who are grounded in their personal relationship and commitment to Jesus Christ.”

– Most. Rev. George Niederauer

Archbishop Emeritus of San Francisco