In a previous article, we looked at the nature of the soul and left off with some important questions. Can the soul continue to exist after the death of the body? If so, can it be destroyed?
Let’s consider these questions here.
The key to answering the question of whether a soul can continue to exist after death is figuring out whether a soul has any activities that transcend the boundaries of matter. Imagine a workaholic who never cultivated a life outside his work. All of a sudden, he’s retired, and he doesn’t know what to do with himself, because all of his activity was bound up with and dependent on his career. This is a way to illustrate the principle that action follows being—that something acts according to its mode of existence. If we can figure out the nature of the activity, then we can know the nature of the thing’s mode of being.
So, if a soul is like the workaholic, and its activities are entirely bound up with and dependent on matter, then its existence will be bound up with and dependent on matter. Such a soul would not be able to continue to exist after “retirement”—or, in this case, death.
If, however, a soul has activities that are not entirely bound up with and dependent on matter, then such a soul would have an aspect of its life that is independent of matter and thus would be able to continue to exist without its body—like the person who has a spouse and a family and hobbies outside his work to fully devote himself to once retirement comes.
For St. Thomas Aquinas, plants and animals do have souls, but those souls cannot exist without the body. His reason is that all the activities of plants and non-rational animals are bound up with and dependent on matter.
Nutrition and growth are obviously bound up with matter. Sensation, even though its powers are rooted in the soul, is necessarily tied up with matter. When we see something, for example, we see this man. We perceive this man being here and not there. We perceive this man being taller than the plant near his foot. We perceive the color black located here, in this man’s hair. Since our power of sight is exercised through the material medium of the eye, our power of sight necessarily always attains its objects under material conditions: particularity, spatial relations, and quantitative dimensions.
But our human power to know by virtue of the intellect is unlike the power of sight through the eye. We’re able to know the form or essence of something in a universal way, stripped of all material conditions. We’re able to know the essence, the nature, or the form of triangularity independent of the material conditions that make up each triangle—their size, color, location, and the stuff each one is made of. Even a triangle’s particularity is excluded from our knowledge of the form of triangularity.
Since our intellects act on universal ideas in a way that’s not under the conditions of matter, and since our intellects are powers of our souls, it follows that the soul has an activity that is, of itself, exercised apart from the body. And given that operation (or activity) follows the mode of being, we can conclude that the soul can exist without the body.
The next question is whether the soul is indestructible. Proving that a human soul can exist without the body doesn’t prove that the soul is indestructible. Sure, the destruction of the body doesn’t destroy the soul, but perhaps there is some other way that the soul could go out of existence.
For example, whatever is made up of parts can break apart. Can the soul break apart? Or perhaps the soul can go out of existence like how a tree goes out of existence when the tree’s matter loses its form as it’s being put through the woodchipper.
Let’s take a look at these options and see if the soul fits the bill.
We know that the soul can’t be destroyed via breaking apart because the soul is not made up of parts in the first place, being that it’s immaterial. We know that this is true given its immaterial activity of intellectual understanding, as demonstrated above.
The soul also cannot be destroyed via being separated from its form. Every material thing is composed of what philosophers refer to as form and matter. For example, a tree is composed of a certain kind of matter—mostly wood— and a certain kind of form—the form of a woody vegetative organism that grows upward with a trunk that produces branches above the ground.
Now, destruction comes when a thing loses its form and is replaced by another. A tree loses its form, for instance, and thus ceases to exist, when I cut it down and throw it into the woodchipper. The matter loses the form that was making it the kind of thing it was—namely, a tree—and takes on the form of wood chips. Therefore, if something can lose its form, and be replaced by another form, then it can be destroyed.
But unlike the tree, which can lose its form due to its nature as a matter-form composite, the human soul can’t lose its form and be replaced by another because it is only a form. For a human being, the soul is the form of the body—that which makes the body a human body. Therefore, when the soul separates from the body, it can’t be destroyed by losing its form and being replaced by another.
Since the soul is a form and therefore cannot be taken away from itself, nor can it be replaced with another form, and we know that the human soul can exist without the body, then it follows that the human soul by nature is indestructible.
There is one last way the soul could go out of existence, and that is by way of annihilation. Annihilation is the reduction of something from existence to non-existence, which is an action that can be performed in principle only by God. Annihilation would not be due to anything in the nature of the soul itself, but simply due to God ceasing to will the soul’s existence.
But we know that God won’t do this, since it would violate his wisdom. It would be contrary to God’s wisdom to create a thing with an immortal nature only to thwart that nature. We can even go so far as to say that given that God has created an immortal nature, and given his immutable nature, he cannot annihilate the soul. He is committed to the nature of the thing he creates.
So the human soul is of such a nature that if it exists, it will exist forever. In other words, it’s immortal. And since we have good reason to think that God will not annihilate it, we can conclude that there is existence beyond the grave.
So the soul is not some sort of metaphysical rug under to cover our embarrassment as we flail around to explain Catholic doctrines on life after death. Rather, the immaterial and immortal soul is a metaphysical rock on which we can build an edifice of faith in Jesus’ promise of eternal life in heaven.