How does the Church respond to the theory of evolution?

In the first place, it’s essential that we understand that the Church and science are not opposed to one another. There is an unfortunately common misconception that in order to be a person of faith, we must reject the advances of science, or conversely to be scientifically credible, we must turn away from faith. St. John Paul II speaks directly against this in his landmark encyclical, Fides et Ratio, in which he describes the relationship between faith and reason as harmonious, like “two wings” upon which the soul rises to heaven. Of course, this raises questions when it comes to understanding the theory of evolution, which seems to stand contrary to the two creation stories of Genesis 1 and 2. How do we understand this?

The Theory of Evolution

Let’s start by making a few clarifications on the theory of evolution–it helps to look more closely at what evolution is and what the theory of evolution actually proposes. “Evolution” simply refers to the process of change in living things (organisms) over time. Change over time is inevitable in species, because in almost all organisms the genes of parents and offspring are unique. With every generation, offspring become more and more differentiated from their ancestors. Over a very long period of time, members of a species that are more equipped to thrive in their environments will tend to survive more than members that are less genetically equipped for the same conditions–with the result being that one group in a species will outlast another. This overall process is known in evolutionary theory as “natural selection,” because conditions in nature “select” (metaphorically) those members of a species whose genes give them an “edge.”

Evolution can also be broken down into two broad categories, macroevolution and microevolution. “Microevolution” is the kind of evolution in which a species undergoes certain changes or adaptations, but still remains the same species. It generally happens within a relatively short span of time, even just a few generations. This can happen in many ways and we have countless examples around us in the real world: the wings of butterflies have been observed to change colors for better camouflage; birds have been seen developing sharper beaks to better suit the food in their ecosystem; horses and dogs are bred by humans to raise offspring more suitable to their owners. “Macroevolution” is where over a very long period of time a species undergoes gradual but significant changes, until eventually it becomes a different species altogether. Macroevolution requires tens of thousands (if not millions) of years, so we have never observed it directly; this is why evolution is still called a “theory,” because however valid/invalid it may be, we haven’t directly observed this kind of evolution. However, we have strong and widespread evidence that this kind of evolution occurs, using things such as genetic research, archaeology, and paleontology. Fossil records tell us about species which no longer exist but strongly resemble certain species of today; over time, the family tree starts to fill in and we can piece together how a species changed and grew over time from previous ones.

Evolution and Creation

So that’s evolution; what does that mean for the creation of the world as recounted in the Bible? Let’s stop for a second and think about what evolution cannot tell us: it can’t tell us why species changed over time, and it can’t tell us what caused species to change. This is where science’s answers end and the answers of philosophy–and religion–begin. Science can tell us how the world works and what the world is made of, but it can’t answer for us why things are there. Philosophy allows us to use the power of our reason to figure out why we are here, but even human reason cannot fully answer that question. The full answer had to be revealed to us–and that is the truth of faith. “Faith” is truth, not opinion–but unlike science or philosophy, it’s not a truth we can discover through observation or reason. It’s a truth that we can only know because it was revealed to us. And who revealed it to us? Simple–God did. To “believe in” God means we have to take him at his word! And since the truths God tells us concern such important things as the meaning of life, our destiny, goodness, and freedom from slavery and death, it’s worth paying attention to what he has to say!

The Bible is one of the two sources of God’s revealed truths to us–the other is Sacred Tradition (but we won’t cover that here). However, God used human authors to give us the truths of the Bible. What does that mean? Well, to put it simply, it means that the Bible expresses truth in our limited human understanding. Imperfect human beings, guided by the Holy Spirit’s inspiration, were the ones who wrote the Bible.

We have to look at how this truth (from God) is being expressed to us by the Bible’s human authors. For instance, when Jesus tells us a parable in the Gospels, and he talks about a shepherd leaving his 99 sheep in search of the one, is the point that this was an actual event which happened to an actual shepherd? No, of course not! Jesus is telling a story to illustrate his point. Other times, though, we might be reading a law or a historical account–in which case the author may be speaking much more literally than Jesus does when he tells a parable. The creation stories in Genesis 1 and 2 are unique because they cross the line between history and folklore. The stories are full of rich symbolism, and yet they also describe events.

There’s certainly room for debate over which portions of the creation stories are literal and which are not. The Church has given some guidance on this matter (mainly in the document Humani Generis); for instance, in section 37, it states that a Christian cannot accept polygenism (the theory that there was more than one “original couple,” or that humanity had more than one origin or beginning). In the previous section, though (36), the Church encourages serious discussion and enquiry about these topics. So these debates are good–but they should never take away from the key underlying point of Genesis. Setting aside what exactly is literal and what is symbolic in meaning, the underlying point of the creation stories, before anything else, is this: God created everything that exists–and he did it with a plan in mind, and he created it all to be good. Furthermore, with regards to the human person, God alone is the origin and creator of the human soul; the origin and nature of the soul cannot be explained away by scientific means.

Conclusion

Looping back to evolution, recall what we said before: evolution is a theory of how organisms change and adapt over time. It can describe the process for us, and it can tell us what makes that process work, but it cannot tell us why that process exists at all. It also doesn’t tell us what began that process, or how life started, or where all the “stuff” of the universe came from. Here’s the key takeaway: however evolution happens, God is still the one who created all life and who continues to guide and sustain it. Assuming that the theory of evolution is completely true, God still was the one who created those species–and if they evolved into other species, they did it under God’s guiding hand of providence. Perhaps we may better call it “supernatural selection” than “natural selection!”

This is especially true when it comes to human beings. Evolution will never be able to explain how humans became rational beings with an immortal soul. Even if we did evolve the way that the theory says that we did, only God could have guided that process so perfectly, and he alone could have given us the divine, supernatural gift of an immortal soul.

So it’s not right or wrong to believe in evolution as a scientific theory which explains things about how the world works. Many brilliant Catholics believe in it. However, evolution cannot explain the meaning and purpose of our lives, or how humanity became what it is today–a creature in God’s image and likeness, with a rational and immortal soul. If the theory of evolution is used to try and reduce the human person to a mere material being without any divine origin, not only is this wrong and against the faith, but it’s not even something which the theory of evolution can account for! Science cannot give adequate answers to these questions. These questions require truth which only faith can supply. When it does so, then we see for ourselves the meaning of St. John Paul II’s words: faith and reason working together to raise the soul to God!