Updated, November 2, 2020: To clarify my point about “evolution” and the word “evolution” near the end of the post.
(Disclaimer: I am not the Church, I don’t speak for the Church nor do I play one on television.) Since it came up in a comment here on the blog and since someone told one of our candidates (actually, it was an entire family!) in the RCIA class that the Church teaches evolution (and they almost dropped out of class because of it), I thought I’d address this profoundly misinformed and often misunderstood notion in a separate blog post. First, let me state clearly that the Catholic Church does not teach any form of evolution whatsoever. The Church teaches religion, not science. That said, the Church does accept that science has much to teach us human beings about the world around us and she does encourage and always has encouraged the practice of science and scientific research. Yes, that’s what I said. Always. She also insists on the honest and ethical practice of science and honest acknowledgment of the limits of scientific knowledge and competence, and that is where some scientists take exception to her having any say at all. Too bad.
The Church acknowledges that it does appear that the world has had a long, long history and acknowledges that things certainly do seem to have changed over long, long periods of time. So the Church has no problem with the idea of evolution of the change-over-time variety. What she objects to is the Darwinian atheistic theory of evolution, which is not mere change over time, but attempts to explain everything about man by materialistic and atheistic means, replacing God with a very God-like “nature” or “natural selection”. This is what the Church objects to and must object to. According to the Church, man has a soul, or, more correctly, is a union of soul and body. According to Darwinian thinking, man is an animal like other animals and has no soul, being composed of matter and that’s it. Everything is to be explained by reducing man to matter. (By the way, St. Thomas Aquinas thought that animals have souls and what differentiates theirs from ours is that ours is a rational soul. See more about this in the weekly series on the soul, specifically, but not exclusively, here.)
And the Church also objects to the idea of beings changing into completely different kinds of beings. Look at the situation we have today. The idea that beings can change into something other than what they are, is becoming more and more widespread. It boggles the mind.
It doesn’t take a genius to see where that kind of thinking will land you. And that, along with the fact that the Church believes instead what God has revealed, is why the Church rejects it, as she does all forms of atheism. Thinking about evolution comes in various varieties, a fact which some people do not seem to realize or perhaps tend to forget. Darwinian evolution is not the only evolutionary game in town, no matter what Darwinists say or how often they say it. So does the Church reject evolution? No, not if what is meant is simple change over time, but not ever the change of one thing into a completely different other. Does she embrace or teach Darwinian atheistic evolution? No, she does not and, indeed, cannot.