top of page
  • Writer's picture Peter Kupisz

Why Do Atheists Trust Their Brains if They Are the Result of a Blind Evolutionary Process?

Should you trust your brain to tell you the truth about God? Or what about trusting it to do complicated science and mathematics?

The answer depends on how your brain got to be the way it is. Or so says the highly respected Christian philosopher, Dr. Alvin Plantinga. The argument that he presents goes as follows. If our bodies are the result of an unguided evolutionary process, then they will have the characteristics that promote survival and reproduction. (This has been described as the four Fs: feeding, fleeing, fighting and reproducing.) Since our brains are part of our bodies, they (along with the beliefs inside of them), will also have the characteristics that promote survival and reproduction. In many cases, this will result in true beliefs. For example, if one of our distant ancestors is on the African plains and he sees a hungry lion, the belief that “lions are dangerous and I better stay away” will help him survive. However, other beliefs, such as whether the stars are far away or very close to the earth, will probably not make much difference. Given this, atheists struggle to explain why they trust their brains to tell them the truth about God’s existence or non-existence. Beliefs about the nature of ultimate reality may have had some minimal impact on the four “Fs” but not any significant impact. Furthermore, why are our brains so good at thinking about complex science and mathematics? This does not seem to have played any significant role in our survival and reproduction. From an atheistic perspective, this is all quite mysterious. On the other hand, if the evolutionary process was guided by God (or if God supernaturally intervened) then the situation makes much more sense.

In response to this argument, the eminent atheist philosopher, Dr. Thomas Nagel, acknowledges that Plantinga has made a good point.

Plantinga is certainly right that if one believes it, the theistic conception explains beautifully why science is possible: the fit between the natural order and our minds is produced intentionally by God. He is also right to maintain that naturalism [atheism] has a much harder time accounting for that fit. Once the question is raised, atheists have to consider whether their view of how we got here makes it at all probable that our cognitive faculties should enable us to discover the laws of nature… when our faculties lead us to beliefs vastly removed from those our distant ancestors needed to survive—as in the recent production and assessment of evidence for the existence of the Higgs boson—Plantinga’s skeptical argument remains powerful… Defenders of naturalism [atheism] have not ignored this problem, but I believe that so far, even with the aid of evolutionary theory, they have not proposed a credible solution.

Learn More


Thomas Nagel, “A Philosopher Defends Religion,” September 27, 2012,



bottom of page