Medieval Geopolitics: The Moral Purpose of the State

By Andrew Latham

As I argued in my last column, by the thirteenth century Latin Christians shared an understanding of governed political community that was corporate, territorial and organic in nature. But what were the ends of such a community? What were the fundamental social goods toward which it was ordered and from which it derived it legitimacy? In short, what was the moral purpose of the later medieval state?

In order to answer these questions, it is necessary to trace some of the main lines of thought regarding the “common good” (bonnum commune, bonnum rei publicum, utilitas publica, etc.), the phrase most often employed in official documents and philosophical writings of the Middle Ages when referring to the ultimate goal or final end of government.  In the late medieval political imaginary, the common good referred to the good of all members of society, as opposed to one or a few. Some thinkers understood it to be the sum total of the individual goods of the members of the community; others as the corporate good of the community as a whole. Some understood it in fairly utilitarian terms (peace, security); others in more ethical terms (justice, liberty); and still others in terms of “sufficiency” and virtue.


Whatever the specific meaning imputed to it by various thinkers, however, there was broad agreement that the common good either was superior to the individual good or that there was no real tension between the two.  There was also a broad consensus that promotion of the common good was the purpose of all authority, temporal as well as spiritual. As Thomas Aquinas put it, “The first duty of the ruler is to govern his subjects according to the rules of law and justice with a view to the common good of the community as a whole.” Indeed, to the later Medievals the commitment to – and ability to cultivate – the common good was viewed as the benchmark of valid law, good government and legitimate political authority.  To answer the question I posed at the outset of the column, the moral purpose of the state was promotion of the common good.

Underpinning, informing and delimiting the diversity of views regarding the nature and content of the common good were two main currents of philosophical reflection.  The first, deriving from the works of St. Augustine, framed the common good in terms of peace, order and security. Contra Aristotle’s views (which he knew only indirectly through the works of Cicero available to him), Augustine argued that the common good had nothing at all to do with the shared pursuit of virtue or morality – indeed, he argued that such a common enterprise was a logical impossibility.  All human political communities, according to Augustine, comprised a mixture of the citizens of the Heavenly City (i.e. the just and virtuous) and the Earthly City (the unjust and vicious).  As these two groups had radically opposed supreme “loves” or values – one, God; the other, man – they simply could not share a common set of fundamental interests, purposes or ends.


In other words, there could be no such thing as the “common good” in the Cicernonian or Aristotelian sense.  All that was possible was a qualified agreement on limited number of intermediate goods that had a “common usefulness” (communis utilitas): peace, concord, “the satisfaction of material needs, security from attack and orderly social intercourse”.  On this view, the communis utilitas was an essentially amoral phenomenon having to do exclusively with the material security and well-being of the community and its members.  The realization of this set of shared objectives in some meaningful measure might, of course, provide a context within which people could act virtuously – Christians could take advantage of it to seek fuller communion with God – but it could also benefit non-Christians pursuing the decidedly more worldly ends of personal glory and material self-interest. Ultimately, for Augustine and those influenced by his thought, the common good (redefined as communis utilitas) was understood in terms of peace and order rather than peace and virtue.

Entailed in this conception of the common good was an understanding of the moral purpose of the institutions through which this good was to be promoted – the state. For Augustine, the moral purpose of the state was restricted to promoting a limited set of intermediate (and instrumental) interests by imposing and safeguarding what he calls “earthly peace” within and between political communities.

Aristotle and the Common Good

Later medieval understandings of the common good and the moral purpose of the state were deeply indebted to, and powerfully shaped by, this Augustinian view of the nature and purpose of political life.  But the political thought of this era was also had an important Aristotelian dimension.  Drawing heavily on the recently re-introduced works of Aristotle (especially his Politics and Ethics), later medieval thinkers such as Albertus Magnus, Thomas Aquinas, Ptolemy of Lucca and Remigio de Girolami developed a concept of the common good that was firmly rooted in the Aristotelian notion of “life of virtue”.

For Aristotle, of course, a truly ethical life – the “good life” – involved the fulfillment of man’s distinctive purpose or nature (telos), which he defined as his capacity both to reason (i.e. to be rational) and to order his life according to the dictates of reason (i.e. to live a life of virtue or moral excellence). Building on this, Aristotle went on to argue that the purpose of associating in political communities was the fulfillment of its members’ distinctively human nature – that is, their full flourishing as rational, moral and social animals – through education and through laws which prescribed certain actions and prohibit others. As he put in the Ethics: “The end of politics is the best of ends; and the main concern of politics is to engender a certain character in the citizens and to make them good and disposed to perform noble actions.”

Aristotle at his writing-desk. Miniature in the manuscript Vienna, Österreichische Nationalbibliothek, Cod. phil. gr. 64, fol. 8v.

On Aristotle’s view, then, the common good of the political community was not merely the provision of the material necessities of life, but rather the promotion of what he called the “good life” (the life of virtue).  Commenting on and applying these arguments in the later medieval context, thinkers in this tradition tended to agree with Aristotle’s definition of the bonum commune: for them, the common good was primarily about moral goodness and the life of virtue.

To be sure, there were significant debates among these later medieval Aristotelians: nominalists like William of Ockham, for example, viewed the common good as nothing more than the sum total of individual goods, while so-called realists tended to view it in more corporate terms. And later Medievals typically disagreed with the Philosopher on the nature of complete human fulfillment: while Aristotle emphasized humanity’s independent capacity to fulfill its own nature, medieval political thinkers assumed and insisted that true fulfillment (beatitudo) was dependent both on God’s grace and, ipso facto, on the Church as a sign and instrument of that grace.  At a very basic level, however, all agreed with Aristotle that the ultimate moral purpose of associating in political communities was to fulfill human nature and enable the virtuous life of the citizenry.

In turn, this less pessimistic understanding of the common good gave rise to a less pessimistic view of the moral purpose of government and the state. In the works of significant political thinkers and writers such as Albertus Magnus, Thomas Aquinas, Brunetto Latini, Giles of Rome and Henry of Ghent we find discussions and debates about the positive role to be played by the state in promoting the common good of the community and its constituent elements.  Contra Augustine, these thinkers argued that the fundamental moral purpose of the state was not to punish and remedy sin, but to promote true human fulfillment (often called in the political context “happiness” or felicitas).


Although there were differences in emphasis, Aristotelian political thinkers argued that this required the state to engage in moral regulation and education; coordinate the division of labour and other discordances inherent in political communities; promote economic security and prosperity; provide welfare for the poor, widows and orphans; uphold the law; promote justice; maintain social peace; suppress vices; and defend the political community against aggression or injury from external sources. They invariably justified such activities in essentially Aristotelian terms: they were necessary in order to create the conditions within which citizens could enjoy lives of peace, order, material sufficiency and moral virtue – that is, to live the Aristotelian good life.  While sin and the Fall were certainly not absent from this intellectual tradition, they played a far less central role in morally grounding the state than they did for Augustine and his successors.

By 1300 these two “political languages” had become fused to such an extent that they constituted a single political language that expressed a single “syncretic”, norm involving both the Augustinian ideal of peace and security, and the Thomistic one of happiness and fulfillment. In other words, by the end of the 13th century, the moral purpose of the state had come to be widely understood as involving the provision of a limited set of public goods necessary to the full flourishing of both the constituent parts of the political community (individuals, families and the Church) and its corporate personality.  Internally, there was broad agreement that the most basic task of the state was to ensure peace.  Emerging largely in response to the twelfth century crisis of feudalism and the bloodshed it unleashed, the state was in effect genetically ordered toward the suppression of private violence, the pacification of the domestic political life of the community, and the regulation of internal conflict.  Reflecting the views of both Augustine and Aristotle, the late medieval political imaginary emphasized the role of the state in promoting “concord” (concordia), defined, not as consensus regarding the common good of virtue, but simply by its opposite, the absence of discord. Concordia, it was generally believed, was a necessary precondition for political community; internal peace and the “tranquility of order” (tranquilitis ordinis) a prerequisite for the benefits of social life.  In the late medieval political imaginary, then, the fundamental end to which the state was ordered was peace and concord (pax et concordia).

Externally, the political community was understood as having moral purposes related to the pursuit of its corporate “common good” within a broader society of states.  In this connection, the most fundamental moral purpose of the state was the defense and security of its associated political community. Aquinas, summing up the common sense of the era, put it thus: “Just as the rulers of a city-state, kingdom or province rightly defend its public order against internal disturbance… so too rulers have the right to safeguard the public order against external enemies, by using the sword of war”.

Beyond this, however, it was widely believed that states were morally obliged to assert, defend and recover the corporate rights of the political community within the broader society of states – that is to jealously guard and vigorously assert what they took to be their customary, feudal or legal rights. Often, this took place within courts or through arbitration.  When these institutions failed, however, states (though not individuals and other non-state actors) were within their rights – indeed, were morally obliged – to take up arms to in pursuit of their cause. But that is the topic of a future column.


Andrew Latham is a professor of political science at Macalester College in Saint Paul, Minnesota. He is the author, most recently, of The Idea of Sovereignty At the Turn of the 14th Century. You can visit Andrew’s website at or follow Andrew on Twitter @aalatham 

Top Image: British Library MS Additional 24189 f. 5


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