You have heard the arguments for God. But what if someone tells you: "Your brain is just wired to believe in God. Evolution built you that way. It does not mean God is real." This is one of the most common arguments students hear in college, and it sounds powerful. Let's take it apart.
Philosopher Daniel Dennett, one of the "Four Horsemen" of the New Atheism, argued in his book Breaking the Spell that religion is a natural phenomenon. He claimed that belief in God is not the result of discovering something true. Instead, it is a byproduct of how human brains evolved to survive.
The argument goes something like this:
This sounds persuasive. But it has a fatal flaw.
Explaining how you came to believe something says absolutely nothing about whether it is true. This confusion is so common in philosophy that it has a name: the genetic fallacy.
The genetic fallacy is the mistake of thinking you have disproved a belief by explaining where it came from. Here is why this is a fallacy:
Apply this to belief in God. Even if the human brain evolved to be sensitive to the possibility of God, that says nothing about whether God actually exists. Maybe God designed the system. Maybe, as Christian philosopher Alvin Plantinga has argued, God gave us cognitive faculties that are aimed at truth, including the ability to perceive him.
The "religion is just a brain trick" argument has an even deeper problem: it destroys itself.
If you claim that religious beliefs are unreliable because they are products of evolution, you have to face an uncomfortable question: aren't your beliefs also products of evolution?
Your belief that there is no God is held by a brain that evolved not for truth but for survival. Your confidence in science, your trust in logic, your conviction that atheism is correct - all of these are produced by the same evolved brain that the argument says cannot be trusted on matters of God.
As C.S. Lewis observed: "If the whole universe has no meaning, we should never have found out that it has no meaning: just as, if there were no light in the universe and therefore no creatures with eyes, we should never know it was dark."
And as Alvin Plantinga has argued more formally: if our cognitive faculties evolved only for survival (not for truth), then we have no reason to trust them on any topic, including the topic of whether God exists. The argument from evolution against religion, taken to its logical conclusion, is an argument against trusting any of our beliefs, including the belief that evolution is true. It saws off the branch it is sitting on.
Philosopher Alvin Plantinga argued that if naturalism (no God) and evolution are both true, then we have no reason to trust that our cognitive faculties produce true beliefs. Evolution selects for survival, not for truth. A creature could survive perfectly well with mostly false beliefs, as long as those beliefs produce survival-enhancing behavior. If so, the naturalist has defeated their own ability to trust their conclusion that naturalism is true. This is now one of the most debated arguments in philosophy of religion.
When you look at the research carefully, the cognitive science of religion does not actually support atheism. Here is what the studies show:
Dennett's Breaking the Spell tries to explain why humans are religious. But it never addresses the actual arguments for God's existence.
Think about that for a moment. You have spent the previous eighteen lessons studying evidence: the universe had a beginning, its constants are fine-tuned, objective moral facts exist, the Bible is historically reliable, archaeology confirms its claims, Jesus existed, he made extraordinary claims, he rose from the dead, and the hard questions have serious answers.
Dennett's argument skips all of that. It does not address the cosmological argument. It does not address fine-tuning. It does not address the resurrection evidence. It just says, "Your brain is wired to believe." Even if that is true, it does not answer a single one of those arguments. It is like telling someone who has done extensive research on climate change, "You only believe in climate change because your teachers told you to." That might explain the sociology of their belief, but it says nothing about whether the evidence is good.
"If religion is a brain trick, it explains why people in every culture believe in gods."
Yes, people in virtually every culture in human history have believed in a transcendent reality. But this is equally consistent with there being a transcendent reality. The universality of belief is actually what you would expect if God were real: he made humans to know him, and humans across every time and place have responded to that design. The universality of belief is evidence that needs explaining, and "God is real" explains it at least as well as "everyone is wrong."
"Science can explain everything about religion without needing God."
Science can describe the mechanisms of belief. It can tell you which neurons fire during prayer, which brain regions activate during worship, and which evolutionary pressures may have favored religious behavior. But explaining the mechanism does not explain whether the belief is true. Science can also describe the mechanisms by which you perceive a sunset (photons, retinas, neurons), but no one concludes that sunsets are therefore imaginary. Mechanism and reality are different questions.
"Children believe in God because their parents teach them to. That proves it is cultural, not real."
Actually, the research shows something more interesting. Cognitive scientists like Justin Barrett have found that children naturally develop belief in a creator even without explicit teaching. They seem predisposed to see the world as designed. But even if belief were entirely cultural, that would not disprove it. Children also learn that fire is hot and that lying is wrong from their parents. The cultural transmission of a belief says nothing about whether the belief is true. Many true things are taught by parents.
What is the "genetic fallacy" and how does it apply to the claim that religion is a brain trick?
Why does Plantinga argue that the "religion is just evolution" argument defeats itself?
The claim that religion is "just a brain trick" commits the genetic fallacy: explaining where a belief comes from does not tell you whether it is true. Even if the brain evolved to detect God, that does not prove God is not there to be detected. The argument also defeats itself: if evolved brains cannot be trusted on God, they cannot be trusted on anything, including atheism. And it never addresses the actual evidence for God. You have spent nineteen lessons examining that evidence. A story about neurons firing does not erase a single argument.