The Conversion of St. Augustine, by Fra Angelico (c. 1395-1455).
How Augustine Made Us More than Matter—and Immortal | Brother Justin Hannegan, OSB | HPR
St. Augustine was fascinated by the human soul. Before and after his conversion to Catholicism, he strove to understand its nature, its relation to the body, and its duration. Augustine’s thinking on the soul, like the rest of his life, followed a tortuous path. In this article, I retrace the steps that led him to his developed understanding of the soul—an understanding that would shape subsequent Catholic teaching.
In his early days, Augustine thought that the soul was a fine material substance dispersed throughout the body. He could not accept the existence of a substance that lacked spatial dimensions: “Whatever was not stretched out in space, or diffused or compacted or inflated or possessed of some such qualities, or at least capable of possessing them, I judged to be nothing at all.”1 Augustine, therefore, starts off a materialist. But he changes his mind upon reading Plotinus, who teaches that God is an immaterial substance. Augustine reasons that, because we are made in the image and likeness of God, the human soul is also an immaterial substance: “when speaking of God, no one should think of him as something corporeal; nor yet of the soul, for of all things the soul is nearest to God.”2
Augustine, however, does not merely rely on the Christian doctrine of the imago Dei to prove his point. Instead, he develops a number of philosophical arguments to demonstrate the soul’s immateriality. One of these arguments is that because the soul’s cognitive objects are not limited spatially, the soul itself cannot be limited spatially; and because the soul cannot be limited spatially, it, therefore, cannot be a material body.3 Another argument is that because the soul thinks and wills, but a material body cannot think or will, the soul, therefore, cannot be a material body.4 A third argument is that we attribute moral qualities to the soul, but moral qualities cannot be spatially extended properties of a material substance (e.g., “justice cannot be three-dimensional”); so the soul cannot be a material substance.5
Augustine’s doctrine of the immateriality of the soul leaves him with a conceptual puzzle: how is the immaterial substance of the human soul related to the material substance of the human body? Neo-Platonic philosophy holds that the soul is independent of the body and, regrettably, trapped in the body, as if in a prison: “the body is (the soul’s) fetter and tomb.”6 The soul’s proper place, therefore, is apart from the body, and it should endeavor to escape the body at the earliest opportunity. Augustine cannot accept this view. His Christian faith teaches that God created man with a body, and that man’s body will rise on the last day and be united with the soul in paradise. So the body is not a mere prison. Augustine must part ways with the Neo-Platonists on this point.
Another option for Augustine is to follow Aristotle, as Aquinas does many years later, by averring that the soul is the form of the body.