The Disfigured Face: The War of the Philosophers: St. Thomas on Slavery

THE SCHOOL OF SALAMANCA was the work of the Dominican Francisco de Vitoria. He has been hailed as the "Father of International Law." He was not trapped by a Spanish parochialism or jingoism; his philosophy, and his Faith, allowed him to overcome many of those nationalistic hindrances that bound the ordinary Spaniard to his belief in superiority or exceptionalism of his nation. It was these sorts of intellectual chains that bound up the intellect of that advocate of natural slavery, Sepúlveda, and made him, in an ironical way, a slave to them. Spain in the early 16th century was the glory of the earth. Headed by the Emperor Charles V, Spain was the world power. It was firmly planted in two continents. It took a great man to seek that there was a part of Spain, its earthly glory withal, that was not glorious in heaven. But Vitoria's merits were largely a reflection of his teacher, St. Thomas Aquinas.

Portrait of Emperor Charles V by Titian

It was his appointment to the University of Salamanca, and his promotion of Thomism there, that was Vitoria's greatest, and lasting work. Unusually, he did not publish any work during his lifetime, and the majority of what we have from him are as a result of notes taken from his lectures. Perhaps his most important, certainly the most frequently read, are his Relectio de indis recenter inventis, his lectures on the status of the recently-discovered Amerindians. Many of these notes, at least those on other topics, unfortunately, remain unpublished.

In his Relectio de Indis, Vitoria addressed the issue of whether Spain was justified in conquering the Americas because of the lapse of reason, the "rational insufficiency," of the Amerindians. Despite their social sins and cultural enormities (e.g., human sacrifice, idolatry), were the Amerindians capable of self-government, self-determination? Or were their cultural enormities, the product of the failure of the natural law and reason, justifications for just war and warrant for conquest? It is clear that Aristotle's authority and stature was the biggest impediment to answering the question. Specifically, the Aristotelian doctrine (found in his Politics and in his Nicomachean Ethics) that there were men who were barbarian, who were by nature slaves, and were naturally lacking in the right over themselves and their possessions. Slavery was rampant in the ancient Greek world, and Aristotle addressed the issue of whether it was a natural institution, or rather one that was conventional. Aristotle believed that slavery was a natural institution, that there were some men, who, by reason of their superiority, were naturally masters, and other men, who, by reason of their inferiority, naturally slaves.

But is there any one thus intended by nature to be a slave, and for whom such a condition is expedient and right, or rather is not all slavery a violation of nature? This is the question: but it is interesting that he feels the need to ask it. There is no difficulty in answering this question, on grounds both of reason and of fact. For that some should rule and others be ruled is a thing not only necessary, but expedient; from the hour of their birth, some are marked out for subjection, others for rule.

Politics, I, 2, 1254a. Vitoria was, as may be expected, conservative, and he struggled to find a way around the Aristotelian doctrine without repudiating it. "Aristotle certainly did not mean to say that such men thereby belong by nature to others and have no rights of ownership over their own bodies and possession (dominium sui et rerum). Such slavery is a civil and legal condition, to which no man can belong by nature." Aristotle "certainly did not mean by this that such men had a legal right to arrogate power to themselves over others on the grounds of their superior intelligence, but merely that they are fitted by nature to be princes and guides." Granting, arguendo, that the American Indians were "foolish and slow-witted as people say they are," Vitoria's conclusions were that it was "still wrong to use this as grounds to deny their true dominion (dominium); nor can they be counted among the slaves." Cortest, 37 (quoting Francisco de Vitoria, Political Writings (Cambridge: Cambridge University Press, 1991), 233.)

Fray Bartolomé de Las Casas by Félix Parra

Vitoria's effort to circumvent Aristotle without outright repudiation has been criticized by scholars, and probably rightly so. To give to Aristotle such a slant was outside the range of probability of Aristotle's intendment.

On the other hand, Las Casas was much less deferential to the Aristotelian "natural slavery" doctrine. Cortest, 38. Las Casas maintained that there was but one human race, "una denique sola species creaturae rationalis, quae in individuis suis per universum mundum erat dispersa," "besides, there is only one species of rational creature, which is dispersed through the entire world in his individuality." (So in his De unico vocationis modo.) Though there may be differing levels of cultural achievements and though they may be laboring under social or cultural impediments, the Indians remained children of God, redeemed of Christ, and fellow brothers with the Spaniards:

Again, if we want to be sons of Christ and followers of the truth of the gospel, we should consider that, even though these peoples may be completely barbaric, they are nevertheless created in God's image. They are not so forsaken by divine providence that they are incapable of attaining Christ's kingdom. They are our brothers, redeemed by Christ's most precious blood, no less than the wisest and most learned men in the whole world.

Cortest, 41 (quoting Las Casas's In Defense of the Indians) Can one imagine Aristotle, the proud Greek, saying of the Persians or the lesser peoples, "They are our brothers"? Manifestly no. Christianity injected something precious, something magnificent, into the world, a comfort to the poor and downtrodden, and a humbling medicine, perhaps bitter in taste, to the rich and the proud. Oh let us praise the Lord God in unison with Mary for the entry into the world of this thing!

Magnificat anima mea Dominum,
et exsultavit spiritus meus in Deo salvatore meo . . . .
Fecit potentiam in brachio suo,
dispersit superbos mente cordis sui;
deposuit potentes de sede,
et exaltavit humiles;
esurientes implevit bonis,
et divites dimisit inanes.

Others also addressed the issue of the Amerindians' status as "natural slaves," and weighed in against Sepúlveda. Among these, Cortest cites and discusses the Jesuit José de Acosta, the so-called "Pliny of the New World," who detailed the natural and moral history of the Indies. He discusses the Dominican Domingo Bañez, the proeclarissimum jubar, the "brightest light" of Spain, and confessor to St. Theresa of Avila. He also briefly addresses the view of the Dominican Melchor Cano, that zealous prosecutor of Carranza and author of the famous De Locis Theologicis. But the real focus of his sights is Francisco Suárez, and the teacher of them all, St. Thomas Aquinas.

In his De triplici virtute theologica, fide, spe & charitate, Suárez explicitly confronts the position of Sepúlveda on Spain's right of conquest over the pagan American Indians. The three arguments commonly given were that such conquest was justified by reason of the Indian practice of human sacrifice, which warranted intervention to defend the innocent. The second argument commonly given was that such conquest was legitimated by the cultural benefits that the pagan society would receive from its conquerors' superior civilization. The third argument (which is the one that Cortest in his discussion of Suárez focuses on) is the argument that the Amerindians were, by nature, slaves, and therefore could be compelled to obedience to their superiors. Cortest, 40.

Aztec Human Sacrifice: Did it Warrant Conquest?

In addressing the last argument, Suárez doubted that, in fact, there could be peoples that were so barbarous and uncivilized "that they were neither united in a civil society, nor capable of exercising government." In other words, the capacity to live in common and provide for self-determination and self-government is so intrinsic to humanity, that one ventures into the land of theory to suggest that a people have lost this capacity. In practice, Suárez maintains, such a barbarous people with an absolute inability to self-govern have never been found.

The fact is that all of these men: Vitoria, Las Casas, de Acosta, Bañez, Cano, Suárez, and literally hundreds of others who are lesser lights but remain within the constellation of the School of Salamanca were schooled by St. Thomas Aquinas. "[T]he reason these writers share a common view concerning the doctrine of natural servitude is that Thomas himself rejected this doctrine." Cortest, 42. It is St. Thomas, steeped in the law and teachings of the Gospel, who overcame the Aristotelian "some men are by nature slaves" blight.

Cortest focuses on St. Thomas Aquinas's Summa Theologiae. Thomas's commentary on Aristotle's Politics is problematic in that it is difficult to tell when St. Thomas is citing Aristotle's text with approval, and when he is not. Moreover, the commentary was never completed. The Summa, though also not fully completed, presents clearly enough St. Thomas's own view on the matter of the institution of slavery. The heart of the Thomistic analysis is Question 57, article 3 of the second part of the second part (IaIIae):

From the bare nature of the case there is no reason for this man rather than that man being a slave. It is only when it is looked at pragmatically in its results that, as Aristotle says, it is expedient for him to be ruled by a wiser man whom he serves. Servitude, which is part of the ius gentium, is natural then in the second sense of our explanation, not the first.

[H]unc hominem esse servum, absolute considerando, magis quam alium, non habet rationem naturalem, sed solum secundum aliquam utilitatem consequentem, inquantum utile est huic quod regatur a sapientiori, et illi quod ab hoc iuvetur, ut dicitur in I Polit. Et ideo servitus pertinens ad ius gentium est naturalis secundo modo, sed non primo [modo].

S.T., IIaIIae, q. 57 a. 3, ad 3. St. Thomas appears, then, to reject the Aristotelian notion that some men, are by nature inferior to others. However, he does not enter into the intellectually vacuous and indefensible territory of those who hold that men are in all things equal. Such a view is, as a matter of empirical fact, untenable. (In fact, in practice, such a belief can cause untold suffering, perhaps even more than the suffering imposed by slavery. One need only look at the sufferings of those under Communism. Wasn't it Gilles Dauvé who said, "Communism believes in equality through force"? Slavery is inequality through force. Communism is equality through force. Both are social and moral evils.) What St. Thomas suggests is that though slavery is not a natural institution, it is natural that some men should be subordinate, but not enslaved, to others, namely, the wiser.

This view is confirmed in another part of the Summa (dealing with the relationship between man and wife). Here, St. Thomas distinguishes between the subordination which is only for the advantage of the master (slavery), and subordination which is for the benefit of the subject (right order):

Subjection is of two kinds; one is that of slavery, in which the ruler manages the subject for his own advantage, and this sort of subjection came in after sin. But the other kind of subjection is domestic or civil, in which the ruler manages his subjects for their advantage and benefit. And this sort of subjection would have obtained even before sin. For the human group would have lacked the benefit of order had some of its members not been governed by others who were wiser.

Ad secundum dicendum quod duplex est subiectio. Una servilis, secundum quam praesidens utitur subiecto ad sui ipsius utilitatem et talis subiectio introducta est post peccatum. Est autem alia subiectio oeconomica vel civilis, secundum quam praesidens utitur subiectis ad eorum utilitatem et bonum. Et ista subiectio fuisset etiam ante peccatum, defuisset enim bonum ordinis in humana multitudine, si quidam per alios sapientiores gubernati non fuissent. . . .

S.T., Ia q. 92 a. 1 ad 3. Slavery, though perhaps prevalent among men, is not a natural institution. It entered the world by reason of man's original sin, and, where it becomes institutionalized, as it did in Ancient Greece, or as it did in Africa, Islam (Islam has the added problem that slavery is justified in the Qur'an and the Sunnah, Mohammed having participated, nay, benefited, nay even relished in orgasmic shudder in the institution, as he had sex with his women slaves. Thus it would appear that slavery, which is against the natural law, has the sanction of Allah, if Muhammad and his Qur'an is to be believed.), or the West during the era of the slave trade and chattel slavery, it is the product of sin: indeed, it is a punishment for having sinned. Slavery does not insinuate itself into a society unless it has compromised the natural moral law:

The difference between a slave and a free man is that a free man is because of himself, as it says at the beginning of the Metaphysics; whereas a slave is geared to the benefit of another. So someone lords over another as a slave when he simply uses him for his own, that is the lord's purposes. And because everyone naturally values his own good, and consequently finds it grievous to surrender entirely to another the good that ought to be his own, it follows that lordship of this kind cannot but be punitive to those subjected to it. For this reason man cannot have lorded over man in the sate of innocence in that sort of way.

Cuius ratio est, quia servus in hoc differt a libero, quod liber est causa sui, ut dicitur in principio Metaphys.; servus autem ordinatur ad alium. Tunc ergo aliquis dominatur alicui ut servo, quando eum cui dominatur ad propriam utilitatem sui, scilicet dominantis, refert. Et quia unicuique est appetibile proprium bonum, et per consequens contristabile est unicuique quod illud bonum quod deberet esse suum, cedat alteri tantum; ideo tale dominium non potest esse sine poena subiectorum. Propter quod, in statu innocentiae non fuisset tale dominium hominis ad hominem.

Ia q. 96 a. 4 ad arg. There is a predisposition in man toward slavery. This is the result not only of the Fall, but also of the natural convenience, the pragmatic benefits to the master from this institution. It is sometimes so entrenched that the removal of it can cause more harm than the tolerance of it. Analogously, it is sometimes better to live, at least for a time, with a tumor, if to remove it would result in certain death. Thus, slavery is something that, though not in accord with nature, is frequently found among human societies. This is because something can be said to be natural in two ways, actively, because nature requires it, and passively, because nature does not appear to forbid the contrary.

You speak of something being according to natural right in two ways. The first is because nature is set that way; thus the command that no harm should be done another. The second is because nature does not bid the contrary; thus we might say that it is of the natural law for man to be naked, for nature does not give him clothes; these he has to make by art. In this way common ownership and universal liberty are said to be of natural law, because private property and slavery existence by human contrivance for the convenience of social life, and not by natural law. . . .

[Q]uod aliquid dicitur esse de iure naturali dupliciter. Uno modo, quia ad hoc natura inclinat, sicut non esse iniuriam alteri faciendam. Alio modo, quia natura non induxit contrarium, sicut possemus dicere quod hominem esse nudum est de iure naturali, quia natura non dedit ei vestitum, sed ars adinvenit. Et hoc modo communis omnium possessio, et omnium una libertas, dicitur esse de iure naturali, quia scilicet distinctio possessionum et servitus non sunt inductae a natura, sed per hominum rationem, ad utilitatem humanae vitae.

IaIIae q. 94 a. 5 ad 3. Thus, slavery was not a natural institution, but one of human origin. It has no divine or natural pedigree. It is one imposed by positive law, by custom, and has entered the world as a result of sin. Though men are, by accidents of birth, culture, education, inheritance unequal, all men are by nature equal, omnes homines natura sunt pares. S.T., IIaIIae q. 104 a. 5 co.

And so it is that this chapter turns to a close:

The philosophical debate concerning the nature of the native peoples of the New World was an important component in the controversy surrounding the legitimacy of the wars of conquest. The legal theory that grew out of this controversy would have a long history. The juridical treatises produced by the members of the School of Salamanca were primary sources for Hugo Grotius and, as such, had a major impact on the development of modern international law. More importantly, the participants in the debate reveal two distinctly different views concerning the dignity of the human person. One one hand, the [strict] Aristotelians (lead by Sepúlveda) defended a hierarchical notion of human worth . . . On the other hand, the strict Thomists defended the idea that no one is a natural slave; all people are children of God and thus, foreign peoples, even if they believe in different gods, are human beings created by God who live in legitimate societies.

Cortest, 47.

From here, Cortest turns to the philosophy of natural right. Specifically, Cortest traces its origin to the 16th century, and, after exploring the origin of modern human rights, will compare it to the classic, specifically Thomist, theory of natural law.

The Disfigured Face: The War of the Philosophers: Sepúlveda v. Las Casas

IN A FAIR FIGHT, JUDGED BY MEN OF GOOD WILL, the natural law will win over error. So it would appear is the verdict of history of the famous "Juntas de Valladolid," the debate between fellow Dominicans Fray Juan Ginés de Sepúlveda (1489–1573) and Fray Bartolomé de las Casas (1484-1566). Were the Amerindians, as a result of their lack of Christian faith, capable of self-government, self-determination? What right, if any, did the Spanish kings have to conquer the Amerindians for violations of the natural law, such as their human sacrifices or their pagan customs? Were the Amerindians "natural slaves" referred to by Aristotle, or were they human beings of equal dignity with their Spanish masters? These were the sorts of matters that were debated between these two redoubtable opponents.


Sepúlveda was a formidable adversary. Born in the town of Pozoblanco, near the city of Córdoba, Sepúlveda received his education at the University of Alcalá, and then later in Bologna, Italy. He was a famous commentator and translator of Aristotle, and a correspondent with the famous Erasmus of Rotterdam. At the age of forty-five, he became chaplain and chronicler to the emperor Charles V (as a result writing a thirty volume work on the emperor's doings, the de rebus gestis Caroli Quinti). Sepúlveda fashioned distinct ideas regarding the Amerindians and the Spanish right of conquest under the doctrine of just war. These arguments were gathered into a volume entitled Democrates, secundus sive de justus belli causis, and a subsequent revision, entitled Democrates alter de justis belli causis apud Indios.

From a scholarly perspective, Las Casas may not have had the laurels of Sepúlveda. But what he lacked in intellect, he made up for in heart and in zeal. Born in Seville, Las Casas's life straddled the discovery of the New World. He witnessed Christopher Columbus's return to Seville after the latter's first voyage. Las Casas's father, Pedro, accompanied Columbus on his second voyage, bringing his son a native Taíno native boy named Juanico. Las Casas spent much of his life in the New World and witnessed the brutal treatment of the native American population. All his life, it seems, he was the advocate of the native Americans against the Spanish colonists. He was the first resident bishop of Chiapas, Mexico. Witnessing first-hand the abuse of the natives by the Spanish colonists, he took it upon himself to intercede on their behalf to Charles V. At first, he sought to ameliorate the plight of the Indians by importation of black slaves from Africa; but he soon recanted this position, and became an advocate for the Africans as well. His natural solicitude for the plight of the Indians reached a climax and resolution after he heard the preaching of Fray Antonio de Montesinos. He resolved to divest himself of any holdings that relied on slave labor and gave up his own slaves. Convinced that the Spaniards had committed an act of great injustice against the native people of the Americas, he pushed for, and obtained in limited fashion, laws and institutional reforms. Since these views were not popular, particular with the rich and influential colonists, Las Casas required tremendous courage and persistence.

The debate at Valladolid was inconclusive at the time, but the passage of time has allowed the conventions of the time to change, and from our vantage point and the vantage point of history, it is now plain that Las Casas was the white knight, Sepúlveda the advocatus diaboli.

Neither man was ever proclaimed the winner at Valladolid, but if history is any indication fo the outcome, Las Casas was the clear winner and Sepúlveda a miserable failure.

Cortest, 36.

Las Casas's views were deeply influenced by his personal experience, his missionary spirit, and the preaching of Montesinos. Yet the Thomistic doctrines of the School of Salamanca were also deep influences on him. Cortest, 36. In his work advancing his views, the Democrates alter, Sepúlveda writes in the form a dialogue between Leopoldo (the interrogator) and Democrates (who advances Sepúlveda's position). Leopold asks Democrates:

Leopoldo: Do you realldy believe that anyone could be condemned by nature to live in slavery? . . . Do you think that the jurists, who (so many times) follow the rule of reason, are speaking in jest when they proclaim that all men are born free and that slavery was introduced afterwards by law?

Democrates: On the contrary, I believe that the jurists speak and act seriously and state their teachings with great prudence . . .

(quoted in Cortest, 33). The jurists and canonists referred to by Sepúlveda are those of the School of Salamanca, among them Francisco Vitoria, Domingo de Soto, and Las Casas.

One may here turn Domingo de Soto's De iustitia et iure, specifically book 4, question 2, article 2:

No law can repeal the law of nature: by natural law all men are born free . . . .slavery is that by which someone is subjected to the rule of another against nature . . . . Slavery is contrary to nature, that is to say, contrary to the firt intention of nature, which would desire that all men live zealously in accord with reason. But when this first intention is lost, punishment follows, in accord with corrupted nature. And one form of punishment is legal slavery.

Nullum ius potest naturalis derogare: naturali autem omnes homines nascuntur liberi . . . servitus sit qua quis dominio alieno contra naturam subiicitur . . . . Servitutem esse contra naturam: nempe contra primam naturae intentionem, qua cupit omnes homines secundum rationem studiosos esse. At tamen ailla deficiente intentione, ex culpa subsequuta est poena, quae est conformis naturae corruptae. Atque inter poenarum genera unum est legalis servitus.

Cortest, 35. The prevalence of slavery and its seeming naturalness, then, was a result of the Fall and the result of personal and communal sin. Under the natural law, under the law of reason, it cannot be justified. It is only blindness that makes us adopt it. It is indeed a form of punishment. If Plato is to be followed (Gorgias, 469b), since slavery involves such injustice, at least in the moral dimension, it is a worse punishment for the slave owner than the slave, who suffers physical evil but is innocent of the moral evil. (One would think, by a sort of analogy, that the prevalence of contraception, homosexuality, divorce and remarriage [serial polygamy], and abortion in our country might likewise be forms of punishment for our personal and social sins. Certainly, none of these are signs of authentic human flourishing.)