Editorial Note: This post is part of our #FaithAndScience series exploring the relationship between science and religion, and is excerpted from the author's textbook Faith, Science, & Reason: Theology on the Cutting Edge, 2nd edition (Midwest Theological Forum, 2019).
In the physical world, it seems that most physical evils occur as a matter of course because of physical good: “The life of the spider is the death of the fly.” Physical evil is so deeply intertwined with physical good that they are impossible to separate. At the same time, we know that, even though we are rational, we are also animals whose brains are physical organs that are necessary for our exercise of reason in this life. So our brains share the same ambiguity as the rest of physical reality. We have instincts and inclinations that can be interpreted as evil from one angle, but never from every angle. In fact, it is possible for human beings to come to understand their instincts and inclinations and to consciously choose between them; to treat those different than us as if they were beloved blood relatives, to confront with logic and truth the false ideologies that threaten to sway our minds toward darkness, and to discipline urges that are contrary to goodness.
The insight that our physical bodies, including our brains, bear the same ambiguities as all of physical reality is not new. While writing his greatest theological work, the Summa Theologiæ, St. Thomas Aquinas puzzled over this strange paradox. On the one hand, he observed, we have been made for perpetual, everlasting happiness, something we are capable of thanks to being created in the divine image, endowed with reason and freedom. In thinking of human fulfillment and happiness, St. Thomas had in mind the great mysteries of our salvation—the resurrection of the body and the eternal joy of communion with God. On the other hand, when he considered our nature from the perspective of our biological makeup, he observed that the human body is not perfectly adapted to our spiritual capacities. Nature, he speculated, gave the best it was capable of, producing a body with features that are useful for rational animals (like sense and touch). But much like a blacksmith might choose iron to make a knife for one set of reasons (iron is hard, for example, and can be made very sharp), he might also regret that same material for other reasons, such as the tendency of iron to rust easily.
And, as it is with the blacksmith’s use of iron to make a knife, so it is with human beings, creatures made in the image of God who are also the products of evolution. We have the proper kind of biological makeup for a rational animal, but due to the very limitations of the material world, this makeup cannot in itself provide us with everything needed to be the perfect embodied image of God. God is eternal and the source of perfect life, but given our fallen nature, our bodies are corruptible; they are subject to sickness, aging, and ultimately death. Also, our reason and freedom are constantly interacting with our animal instincts and inclinations, and these are not always easy to harmonize with knowing the truth and loving freely. Thanks to the gift of reason, we are capable of understanding what intellectual, moral, and physical excellence entails, but we so often cannot be our “best selves,” choosing rather to do what we know we ought not to do.
It is utterly incorrect, however, to conclude that what we received from evolution has made us intrinsically evil. It has made us only what any biological process can produce: a creature that pursues survival, physical health, sensual pleasure, and other goods. These are sufficient for an animal existence, and even the bad tendencies we discover in ourselves arise only in relation to the goods that we strive for by nature. But, as St. Thomas also knew, God made us capable of knowing the difference, of being able to “make judgments about our judgments.” In addition, the Christian perspective of God’s intention for humanity offered St. Thomas an insight that science and philosophy, left to themselves, could not provide.
In summary, we receive ambiguous inclinations from our animal nature that are not yet moral or immoral, but can become so through our own free choices. The very things that lead us toward bonding and generosity can also tempt us to mistrust, suspicion, and even hatred. Some scientists suggest that such evil is simply part of human nature. They ask how “sin and death” can be the result of the Fall when clearly we find lust, aggression, killing, and death among animals for hundreds of millions of years before humans came along. But, as St. Thomas’ insights reveal, these inclinations are not in themselves sinful. As long as they are properly directed by reason, there is no sin—the same inclinations which are involved in lust and aggression are also involved in true sexual love and in daring acts of heroism, respectively. And yet, these ambiguous inclinations also reveal that our evolutionary heritage alone is not sufficient for us to be the virtuous, loving, and sinless human beings God created us to be. As our Catholic tradition tells us, God had more work to do.
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