Where did the human mind come from? Some hold that it is merely the product of evolution, that the human mind developed because it proved to be adaptive. It is, they think, a tool that allowed our hominid ancestors to live long enough to reproduce.
Now, you can add to this view that God in some way guided the evolutionary process. Perhaps, for example, He caused certain mutations that He knew would lead to the minds we have today. In that case, it is rather likely the human mind is capable of getting at the truth. Indeed, we generally trust that the things we see are really there, and this trust seems perfectly rational. If God created the human mind, that certifies the trust we place in it. Since God would want us to know things about the world, He would design our minds accordingly.
But you might think that evolution, even without God, would give us reliable minds. After all, suppose that, whenever you saw a ferocious tiger, you believed it was your favorite uncle. You would not live long in the tiger-haunted savannas. Neither would the person who mistook fire for water, or cold for heat, or poison serpents for long-lost lovers. So, it seems at first as though evolution doesn’t need God’s help; all by itself it would give us reliable minds by weeding out the unreliable.
However, the Christian philosopher, Alvin Plantinga, argues this is mistaken. When we see why, we end up with one of the most interesting arguments for the existence of God, the so-called Evolutionary Argument Against Naturalism (affectionately, EAAN).
Here, Naturalism is the view that nature is all there is; there’s no God or souls or anything beyond the physical. But really, Plantinga's argument is not just against naturalism; it shows something positive. It shows that God has stooped to shape our minds.
You might be thinking, “Oh boy, another Christian hung-up on evolution.” But this is not an argument against evolution per se. It is an argument against the view that evolution produced human beings without any help from God. For all that says, much of evolutionary theory is entirely legitimate, not to mention consistent with a nuanced reading of the Bible.
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So here’s how the argument goes. First, evolution cannot directly select for true beliefs. It can’t look into a person’s brain and say, “this one’s a flat-earther! Cull him, my lions.” Rather, evolution can only select for adaptive behaviors. It is not what you think but how you act that determines whether you perish in the trackless wilds. If you see a tiger and think, “Wow! My favorite uncle!,” that in itself won’t get you killed. It’s when you run to the tiger and attempt the secret handshake—that’s what gets you killed. False thought is dangerous only when it leads to foolish action.
The lesson here is that evolution can select for true beliefs, only if false ones would lead to maladaptive behaviors.
But here’s the trick: False beliefs needn’t lead to maladaptive behaviors. To see this, consider that beliefs by themselves do not lead to behaviors at all. They do so only when paired with desires. So, if you believe there is a cookie in the cupboard, that will not lead to cookie eating. You must also want to eat the cookie. If you find cookies disgusting, or if you could care less, or if you were on a diet, then the belief that there is a cookie in the cupboard will lead to a different behavior.
Return now to the tiger-haunted savanna. You see a tiger, you believe there is a tiger, you believe the best way to avoid it is to flee. But these beliefs, though true, do not cause you to flee. Not by themselves. We must add that you want to avoid getting slashed to ribbons. If, instead, you yearn to be devoured by such a noble creature, you might just kneel and wait.
Imagine, then, that you see the tiger, but you never actually figure out that it’s a tiger. To use Plantinga’s example, maybe you believe it’s a big cuddly pussy cat, and while you desire to pet it, you also believe the best way to pet it is to run away from it. This, too, will get your limbs in the right place. You don’t have to form true beliefs in order to survive.
In general, for any adaptive behavior, there are an enormous range of belief-desire combinations that would lead to that behavior. Some of those belief-desire combinations involve true beliefs; many more involve false ones.
Consider the act of apologizing. This is pretty adaptive; it keeps people on your team, and we survive in teams. But evolution could reliably program this behavior by using bizarre delusions. Try this: Every time you’re guilty of something, you falsely believe you are innocent. Naturally, you desire to give your accusers a piece of your mind, to really rip them a new one. But you also believe the best way to do this is to humbly ask their forgiveness. A bunch of false beliefs, combined with the right desire, can easily lead to adaptive behaviors.
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Here is the problem. Since evolution can only select for adaptive behaviors, this gives it no way of preferring true over false beliefs: Adaptive behaviors are consistent with either. Accordingly, if our minds are purely the product of evolution, they are the product of something that has no way of preferring true over false beliefs. Unguided evolution is not likely to craft our minds into reliable instruments for discerning even simple truths about sticks and stones.
If you believe in unguided evolution, then, you should think our minds are probably unreliable, and that means you should doubt all your beliefs. But that would include your belief that the human mind is the product of unguided evolution. And that is self-defeating. And it’s ridiculous to hold self-defeating beliefs. So, you should not believe the human mind is the product of unguided evolution.
The Christian is in a much better position here. The Christian thinks God has shaped the human mind and engineered it to basically get at the truth, at least within a limited niche. God wants us to be able to form significant relationships, to make significant decisions, and that requires a basic grasp of reality. Are we infallible? Of course not. Do some people have thoroughly broken minds? Yes. For Christians this is part of the ravages of sin. But the point remains that in general a mind shaped by God would be aimed at the truth, while a mind shaped only by evolution could be aimed at just about anything. God exists, we may conclude, because without Him we lack knowing minds.
Further Reading
Why do you think God can not be near sin?