How Aquinas helps us understand private property and the common good

This past Sunday the reading from the Gospel of Luke ended with a bang. Jesus warned the great crowd of people traveling with him, “[A]nyone of you who does not renounce all his possessions cannot be my disciple.” 

This was not the only time that Jesus warned his audience about the great perils of wealth. As reported in Matthew’s Gospel, Christ exhorted those listening to his Sermon on the Mount not to store up for themselves treasures on earth, but to store up “treasures in heaven, where moths and vermin do not destroy, and where thieves do not break in and steal.” Then, more radically, He told His listeners, “do not worry about your life, what you will eat or drink; or about your body, what you will wear.” The pagans worry about such things, Christ explained, but those who have faith in God should trust in His providence: “Therefore do not worry about tomorrow, for tomorrow will worry about itself.” 

These words seem to present a real challenge to the way of life of many Christians. Who does not “worry about tomorrow”? Who does not worry about what they will eat or drink? In light of the Sermon on the Mount, what are we to make of, say, the simple practice of saving wealth to provide for the needs of one’s dependents?

These radical warnings call to mind a possible tension between individual ownership of private property, which the Church has long championed, and a central principle of Catholic Social Teaching (CST), namely, the universal destination of the earth’s resources. We can make sense of Christ’s warnings regarding wealth, and reconcile these two seemingly conflicting pillars of Catholic thought, by resort to a helpful framework of moral norms governing property laid out by Thomas Aquinas. 

Man’s right to own property is rooted in general justice—in this case, the advantages that the appropriation of specific things to particular people brings to the community as a whole. The benefits of private versus common ownership of things include clarity as to responsibility for caring for particular things, efficient management of resources, and the avoidance of discord stemming from multiple ownership claims to the same item. But Aquinas draws an important distinction between the right to manage or own resources and the right to use or consume them. While it is just for a society to protect private ownership rights, those rights are always subject to the proviso that the ultimate use of resources must remain fundamentally common. 

Aquinas reconciled the tension between individual property rights and the common destination of all resources by categorizing property into three distinct types. First, there are resources necessary for one’s very survival and that of one’s dependents; we can call these resources absolute necessities. Second, there are resources not essential to survival but rather to fulfill one’s obligations to support one’s family, maintain one’s professional life and status, educate  one’s children, and other such duties; we can call these relative necessities because what is needed in this sense will vary according to one’s personal vocational commitments. Third, there are those resources which are left over after one has provided for one’s absolute and relative needs; we can call these resources superflua (or surplus goods). 

With these distinctions in mind, Aquinas explains that (1) everything one has is held in common by those who need one’s resources to meet their absolute necessities. Such people have a moral claim as a matter of justice to either be given or to avail themselves of one’s property to meet their basic needs. Further, (2) one’s superflua are held in common in that one has a duty of justice, not charity, to dispose of them for the benefit of those in need.

This framework entails that people in dire need, whose situation could reasonably 

be considered life-threatening, are entitled to take others’ private property to relieve that need. From the owner’s perspective, then, one has a correlative duty of justice to relieve dire need by giving not only out of one’s superflua but also out of one’s store of relative necessity goods. 

In situations where no one—or at least, no one in reasonable proximity to oneself and whom one is in a good position relative to others to help—is in dire need, our right to keep and consume our property extends only as far as our relative necessities demand. Superflua should be made available to those who are unable to meet their own relative, vocational needs. 

A key issue in Aquinas’s schema concerns the line between superflua and relative necessities. That line is an indeterminate one, because it is linked, I would argue, to each individual’s personal vocation. The linking of personal vocation to what constitutes superflua, and the corresponding difficulty of making bright-line judgments regarding what is and what is not superfluous, means that rationalizations about one’s holding of wealth are hard to resist. But there must be limits to one’s ability to rationalize this if the principle of the universal destination of Earth’s resources is to have any real bite. 

In his book Aquinas, John Finnis explains how one might measure needs:

Not the emotionally motivated expectations and patterns of consumption conventional among one’s social class, nor exaggerated fears about possible future penury, but the bona fide judgment of a practical reasonableness which includes, as always, general justice and love of neighbor as oneself.

The indeterminateness of the line between necessity and superflua thus does not render the duty to distribute surplus goods less binding, and in making such determinations one is to be guided by practical reason and to spurn emotionally-motivated rationalizations.

The framework described above, borrowed from Aquinas and echoed in some respects in CST on the universal destination of the earth’s resources, illuminates the meaning of those radical warnings from the Gospels noted at the outset. In this case as in others, principles of natural reason come to the aid of our understanding of revelation. 

Those principles help us to see that not all of us are called to divest ourselves of all material goods, as a literalist reading of the Sermon on the Mount might suggest. Neither should we make the mistake of thinking, as many of us often do, that our surplus goods are to be made available to those in need only as a matter of charity, and not of justice. 

In other words, we should not take Christ’s words to mean that we all are called to sell all that we have and live lives like that of St. Francis of Assisi. Some are called to that life, to be sure; most are not. The Gospel message from this past Sunday is properly interpreted, in part, as a warning against disordered attachment to material goods that would prevent us from following Christ. Indeed, Christ’s words and the moral norms governing our holding of property set out by Aquinas remain relevant for all of us, and call us to be more mindful of the ways in which we dispose of whatever amount of wealth we have. 

Tim Bradley is a third-year law student at Notre Dame Law School. You can contact him at