Evolution and the Human Soul

The LORD God fashioned the human being (Hebrew: āḏām) out of the clay of the ground (Hebrew: āḏāmah), and breathed into his nostrils the breath of life, and so he became a living being.
—Gen 2:7

This single line from the Second Creation Account in Genesis offers a rich field of reflection in light of recent advances in our understanding of the evolutionary beginnings of our species. The connection between the word for “ground” (āḏāmah) and the word for “human being” (āḏām) suggests that humans are naturally made of physical elements. Therefore, we will first look at the scientific account of how human beings came from the ground like all other creatures, from a long natural evolution from earlier living creatures. On the theological plane in this process matter, the stuff of the ground, is ultimately fashioned into humanity, the image of God. That tells us a great deal about what it means to be human.

We should note that the passage from Genesis also says that God breathes into the human being his own “breath.” This sets humans apart from the other animals, who also have the breath of life (See: Gen 6:17), but not as breathed directly from God. The picture, then, is of an animal that has a life more like God’s than the rest of the animals, an animal who is not simply one of God’s creatures but who becomes a “living being” precisely because of a special relationship to God.

The Hebrew word for “being” in Genesis 2:7 is nephesh, a word that can be translated as “soul” or “life principle,” which the Church teaches is different from any other life principle we see among other animals, because it is capable of things that are qualitatively different and even survives death. But more about that later.

The biggest issue here is how do we bring these two ideas together? How is it possible to look at a human being as both an animal, and the unique image of God with a soul that does not perish at death? We will therefore conclude with the suggestion that in human origins, and in every human conception, God our Creator is involved in a unique way that is different from the way he is present to the rest of creation—unless, of course, other rational animals are out there somewhere in the cosmos.

So, let us start with what evolutionary science tells us by recalling a fossil-hunting expedition that occurred back in the year 2000 in Ethiopia. While fossil hunting, the scientists spotted a small skull peering down a slope. Years of painstaking excavation revealed other bones as well: a torso, a foot, a kneecap, and tiny finger bones. The skull even contained teeth, which, upon further examination, were revealed to be baby teeth. They named her “Baby Selam”—selam means “peace” in Ethiopian.

Scientists estimate the age of the bones to be 3.3 million years old, making it the world’s oldest fossil of its kind. When you see it, you immediately think, “Wow, that looks just like a chimpanzee baby!” But there is a big difference—this baby had an upper skeleton and skull with chimpanzee-like features, including shoulder blades that would be useful for climbing. But she also had a lower skeleton like ours, which meant she could walk upright naturally. When you watch YouTube videos you can see the difference between how a monkey walks and how we walk. You will notice that Baby Selam’s species walks like us—her lower body is built for walking. In a sense, the journey towards being human started from the bottom up. The discovery of Selam corresponded with others in 1976 Laetoli, Tanzania. There 3.6 million-year-old fossilized footprints were discovered that had been made by a group of three australopiths who traveled across open land through volcanic ash between one wooded area to another. The footprints indicate that their feet and walking patterns were like ours.

From here, we see other traits emerging. We find what are called obligate bipeds—hominins that have bodies that are built for upright walking all of the time. Also stone tools, such as handaxes, are found. The earliest ones are haphazard, but as time goes on they become more and more refined. Those tools were used for killing and butchering animals, so some time in there they started eating meat, which meant that more metabolism could go to brain development. The skull size starts to grow. We also see evidence of prosociality, the caring for other members of groups who could not care for themselves.

In the ruins of the medieval town Dmanisi, in the Republic of Georgia, archaeological digs unearthed artifacts and fossils of Homo Erectus, a hominin species which originated around 1.89 million years ago and only went extinct as recently as 40,000 years ago. One skull, dated to approximately 1.8 million years ago, belonged to an aged male whose tooth sockets had shriveled and who had been toothless (except for one tooth) for many years before he died. For him to have survived without teeth for so many years would have required care on the part of his relatives, in which soft foods were chosen, reserved and probably even chewed for him.

Up until Homo Erectus, all the fossils we find are in Africa, but Dmanisi is thousands of miles away. With new ways to get around, bigger brains and social cooperation, they came out of Africa and spread all over Europe and Asia, even down into the islands of Indonesia.

In Europe, at least 400,000 years ago, their descendants, Homo Heidelbergensis, began building dwelling places with hearths for burning wood and cooking food. They also crafted projectile hunting weapons such as wooden spears. Such spear making required a high level of intelligence and manual dexterity, and spear hunting for large game requires an incredible amount of group cooperation and coordination. These were the ancestors of the Neanderthals, but scientists also trace our own species back to them, but in Africa, not in Europe. So we have taken a detour out of Africa, but we have to go back to continue our part of the story.

Around 300,000 years ago, we begin to see the distinctive anatomy of modern Homo Sapiens, especially in skulls found in Northern Africa and in the Levant, around the Holy Land. But up until 120,000-60,000 years ago, such remains are found accompanied by artifacts that do not differ in any significant way from our Neanderthal cousins, who themselves were not much more advanced than Homo Heidelbergensis. It seems that our modern human skeletal structure, including our large skull cases and brains, were around for a long time before any robust evidence of human uniqueness “arrived.” The oldest example we have of a new kind of behavior comes from Blombos Cave in South Africa from around 77,000 years ago. The pieces of ochre found there, which have a cross-hatch pattern, are the oldest known examples of an artifact that can be confidently interpreted as symbolic. There is no way to know whether or not it was the very first.

What seems clear is that the humans at Blombos existed on our side of the cognitive breakthrough often referred to as the “Human Revolution”—the emergence of symbolic thought, the ability to organize the world around us mentally by generating a vast array of symbols in which one thing stands for something else. The word symbol comes from the Greek verb symbállein, which means “to put together”—in the Blombos Cave, a design appears that shows up in later artifacts and seems to be put together with the intention to stand for some other thing. Once we see symbolism, we are seeing the work of other human beings like us. Consider such 30,000 to 40,000-year-old artifacts and ask yourself, “What other animal does stuff like this?”

We will consider that in a moment. Here is a good opportunity to pause and look back at our guiding verse, especially, “The Lord God formed the Adam, the human, from the earth.” God’s preparation of the human body took millions of years; in fact, it took billions of years of cosmic history for just the first lifeform to evolve on earth. It involved the slow process of primate and hominin evolution, a process that unfolded with fits and starts, with detours and many side-roads. But the delay came not on the part of God but on the part of creation itself, which took time to realize its potential to produce a being capable of being the image of God. Matter had to “mature,” starting all the way back at the Big Bang, to the point where its organization had been realized just so. At that moment, when evolution had produced a brain capable of the processes of language and symbolization, we now no longer speak of hominins but of humans in the fullest sense, rational animals in whom the life-pattern of hominins is taken up as the foundation of a new and greater way of being and acting.

Now you might be thinking, “Wait a minute! You just showed us creatures that make tools, that build houses, that cook meat, that care for their sick and elderly. Neanderthals, whom we did not talk about, even buried their dead. What makes us so different?” The difference is the difference between animal intelligence and human reason.

St. Thomas Aquinas, one of the greatest thinkers in history, saw this difference clearly, and he saw it without disregarding the incredible mental powers of animals. He was aware of a very high degree of cognitive ability, what we might call intelligence or brainpower, in non-human animals. They have the ability to learn from past experience. They are capable of judging situations correctly and can learn to solve problems; St. Thomas called this “natural judgment.” But, the power of reason allows our species alone to make judgments about our judgments, to hold real things in our minds mentally and to come to understand them not only for how they concern us and how we might use them, but for what they are. Animals can make natural judgments, St. Thomas acknowledges, but he also adds, “to pass judgments on one’s own judgments belongs only to reason.”

And, so humans are also capable of freedom and moral responsibility. Because I can make judgments about my judgments, I am responsible for my actions. I can choose to do this or that because I can stand back and think about the nature of this or that choice in itself and in relation to goodness.

Symbolism and language are at the heart of what it means to be a rational animal. Other animals may act intelligently, and make natural judgments, but we human animals have the power of reason—the ability to capture some aspect of a thing in an abstract concept or symbol and to then reason with respect to it to develop a deeper comprehension of both it and how it relates to other things.

What are some examples of the incredible difference between us and all other animals, even our highly sophisticated evolutionary ancestors?

  1. Abstraction: The capacity for objectivity is the human “ability to go beyond immediate interests and needs and to perceive oneself and others as the beings they are in their own right”
  2. We can entertain universal concepts like circularity, redness, beauty, truth, and draw from them principles that apply in all instances of each
  3. We can judge the truth of assertions, like 2+2=4 and then apply it to all such combinations of quantity. A computer can also distinguish between true and false propositions, but only when a human with understanding builds it and programs it to carry out such steps in an automatic way. Unlike a computer, we can reason correctly about true or false propositions even when we have not been programmed to do so, that is, even when we have never been given a precise set of instructions telling us exactly what to do
  4. We are capable of coming to the conclusion that some things are necessarily true. 1 does not equal 0, and we know that this must be the case in any possible universe
  5. Reminiscence: we can submit our memories to reason, and see that we misunderstood in that moment but understand better now

In other words, humans have capacities that transcend the powers of the other animals. Our intellectual powers transcend purely material applications and have infinite applications.

How do we make sense of such incredible capacities which, as far as we know, belong only to us in the universe? Now we can move to consider a second issue: the soul. At Blombos Cave, we no longer simply find the remains of evolutionary ancestors but of humans like us. St. Thomas Aquinas concludes that “There exists, therefore, an operation of the soul which so far exceeds bodily nature that it is not even performed by any corporeal organ; and such is the operation of the ‘rational soul’” (ST I.78.4). The human brain does not reason. It just so happens to be the material organ without which we could not reason. There is more to human beings than physical bodily stuff, even more than the brain.

The issue of the origin of the human soul is the one issue about which the Church has qualified her openness to what science has revealed about our evolutionary origins. To quote St. John Paul II, “The doctrine of faith affirms that man’s spiritual soul is created directly by God . . . the human soul, on which man’s humanity definitively depends, cannot emerge from matter, since the soul is of a spiritual nature.” So, from the theological perspective, the “human difference” is located in the fact that the soul is spiritual and directly created by God; it is not merely the result of a biological process. In fact, this is the case for every human being; whenever a new human being is conceived, it must involve the direct creation of the soul of that human being.

So now it is time to bring it all together, by asking: How does God “directly create” a human soul? In our ordinary way of thinking, it is easy to imagine that whenever a human body is “made,” God makes a soul for this body as a separate thing, “attaching” the two. Many mistakenly think of themselves as two things, a living body and a mysterious ghost that is the real self. This, however, is to misunderstand the nature of the soul, which is not a separate thing that God makes but, along with the matter from which our body is made, is one of two principles that make a human being a living being. No part of us is simply soul, no part of us is merely body. In fact, a body without a soul is not a body at all. As the soul is the very life principle of a living body, a body without a soul is only a corpse.

At the beginning of our species, and indeed at the beginning of every human life, we have a paradox. From one perspective, human beings are the natural product of primate evolution, the end-result of a meandering process that involved trends we see in other hominins: bigger brains, more sophisticated tools, social organization, etc. From the other perspective, each human being is a rational and spiritual being, the product of God’s loving initiative that engages each of us in a special relationship with our Creator. The International Theological Commission (ITC) expresses the mystery of the direct (also called “special”) creation of the human soul in a way that sheds light on this paradox: God can “bring about effects that transcend the capacity of created causes acting according to their natures” in which God directly causes the soul in a “non-disruptive” way.

Human souls, then, do come from parents; through the fertilization of the female ovum by the male sperm, human parents are the created causes acting according to their sexual natures. What makes human reproduction different is not that God disrupts this process, but rather causes it to produce a life principle that transcends that of the other animals. The human soul, the very life-principle that makes a human body to be a living body of a specific kind, is not a thing God makes separately. Rather, due to the free unfolding of a universe that God sustains in being precisely for this purpose, a body of the human kind is, of its essence, a body that must have a spiritual soul to be the kind of creature that it is. It is a body that, in the words of the seventeenth century Catholic philosopher John of St. Thomas, “calls out to God out of justice for a soul.” The spiritual soul is the principle that, with the body, makes a human being this kind of living being. Evolution, according to the God-given laws of the universe and due to the activity of creatures over millions of years, has yielded a situation where, in our universe, there is now a material creature for whom to be spiritual is its natural state, whose origins implicate God and require his direct involvement.

This wonderful mystery reveals a truth that science could never discover but which faith and reason together can discern: that Homo Sapiens is the ultimate reason for why the universe exists, the point of God’s creative activity. From all eternity God did not merely will to share his goodness with creatures, but he willed for there to be a creature that could receive the gift of the created universe and, ultimately, the gift of his own divine life, with understanding and freedom. In the words of St. John Paul II:

Creation is a gift because man appears in it, who, as an “image of God,” is able to understand the very meaning of the gift in God’s call from nothing to existence . . . Man appears in creation as the one who received the world as a gift, and vice versa, one can also say that the world has received man as a gift.

The created universe could not be a gift unless there was a creature who, being capable of understanding, could wonder at its beauty, respond to it with delight, and begin to comprehend its patterns and laws. The human difference, and the paradox of special creation, lies precisely in this uniquely human capacity, which places us in an intimate relationship with the Trinity, who calls us into being out of nothingness and then calls out to us in love.      

I would like to return to our opening verse, Gen 2:7. As I noted, the first part, God forming humanity from the clay of the ground, shows us one more feature of what God has revealed to us, and what evolutionary science also demonstrates—all human beings are from God’s good earth. No one of us can say, “I, or my race, is somehow better than all others.” In the words of Pope Benedict XVI, “Despite every distinction that culture and history have brought about, it is still true that we are, in the last resort, the same . . . earth, formed from dust, and destined to return to it . . . The Bible says a decisive ‘No’ to all racism and to every human division.”

So does science: it turns out that all human beings are 99.9% genetically the same and that the differences between races and ethnicities are vanishingly tiny. A study conducted in the early part of the last decade tested the DNA of 1,056 people from 52 populations in five major geographic regions of the world: Africa, Eurasia, East Asia, Oceania, and the Americas. The study shows that of the tiny 1% difference, 94% is among individuals of the same populations, and only 6% between individuals from different populations. By comparison, according to Ian Tattersall, a single population of chimpanzees in West Africa has more diversity in its DNA than the entire human population has today! Skin color, which has been and remains a source of social division and an ocean of misery, violence, and misunderstanding throughout history, turns out to be a micro-adaptation to various climates that has actually been independently acquired numerous times by human populations living in various regions of the world. Our current crisis has an answer, the answer of faith and of science, that we need to heed.

EDITORIAL NOTE: Our special thanks go out to the Lumen Christi Institute where a version of this essay was originally delivered.

Featured Image: Jacek Malczewski, In the Cloud, 1894; Source: Wikimedia Commons, PD-Old-100.


Christopher Baglow

Christopher Baglow is Director of the Science & Religion Initiative of the McGrath Institute for Church Life at the University of Notre Dame. He is the author of Faith, Science and Reason: Theology on the Cutting Edge and is the co-recipient of the 2018 Expanded Reason Award in the Teaching category.

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