Does the Argument from Reason miss a true understanding of genetic mutation?

“One absolutely central inconsistency ruins [the naturalistic worldview]… The whole picture professes to depend on inferences from observed facts. Unless inference is valid, the whole picture disappears… nless Reason is an absolute–all is in ruins. Yet those who ask me to believe this world picture also ask me to believe that Reason is simply the unforeseen and unintended by-product of mindless matter at one stage of its endless and aimless becoming. Here is flat contradiction. They ask me at the same moment to accept a conclusion and to discredit the only testimony on which that conclusion can be based.”

—C. S. Lewis, “Is Theology Poetry?”, The Weight of Glory and Other Addresses

So, basically put, reason cannot exist if created by something random and without reason.

But genetic mutations happen in millions of different forms: the surviving mutations in our genes are the ones (unsuprisingly) that survive. So genes that are good at surviving: live…genes that are bad (or even apathetic)= zap.

This would explain why a creature, on a larger scale, has reliable logic…because, if it’s data about the world or how to survive within it wasn’t proficiant, the creature would perish: end of that line. The creature with good logic not only gets to live but has a better chance of creating offspring.

Now, I’m not saying Lewis (and other defenders of the argument) was wrong…but I don’t quite see yet how he was right, if seen in terms of evolutionary theory?

For, if seen via genetic mutation, at first glance it looks very much as though logic is eventually inevitable for a species who’s primary tool for survival is planning and thinking ahead, rather than fast legs or strength.

This isn’t really an argument against Tom’s post, but rather an assumption that his premise is wrong. If your assume that rationality cannot arise from the material world, then of course you’ll conclude that evolutionary forces couldn’t have produced rationality.

Correct. I simply added relevant information.

My basic conclusion would be that material cannot create immaterial.
Only God can create the immaterial soul with its powers of intellect and will. By the way, it is the spiritual rational soul which defines human nature; thus distinguishing it from all other living organisms. (Genesis 1: 28; *CCC * 356)

I don’t fully understand how we can claim the mind is not of many evolved modular adaptations…I (persoanlly) believe there IS a none pysical element…but it seems sensible to admit that neurons, genes and matter dictate HOW we think. If you bash a brain (don’t!) it will damage its thought. Energy (in certain areas of the brain) spike whenever specifc thoughts are had…and do so in specific regions that, tested again and again, will react during that ‘a type’ of thought: with every type always causing the same area as before to ‘flare,’ so to speak.

Surely we cannot possibly say that the brain is not the cause of thought:confused:? (I realise it cannot be thought itself)…

Suppose that pre-humans existed. Why and how would their brains self-upgrade? How would we test that idea? Modular adaptations could be assumed but without actual data, it is mostly assumption.

Yes, today, the brain can be imaged. In the past? No. Current brain mapping technology is advancing our understanding of how living brains work. However, what causes thought has two possible explanations: one involves mechanistic naturalism only, and the other involves a natural organ with abilities beyond the proper interpretation of outside stimuli.


Random genetic mutations within the brain are either good at surviving in which case they live and breed…or not good at surviving, in which case no more of that mutation. That’s how pre-human brains upgraded.

The brain can be thought of as being like a computer or DNA. It can only be assumed that the right upgrades occurred at the right places and were successfully integrated into a networked system. As it is currently thought, no planning was involved, as opposed to an intelligent agency that could write new programs and even introduce physical upgrades (like adding more RAM). The idea that those who survived did and those who were not upgraded correctly, and did not, cannot be tested.


Well, not necessarily “the right” upgrades. If we’re taking the position that the universe works somewhat randomly and the world need not have ended up as it has, then it could be that brains could have taken a fundamentally different turn some time in the past 500 million years or so (which is about how long brains have been in the fossil record). A change didn’t have to follow a path leading to the brains we see today- it just had to offer some kind of incremental improvement.

And I think it’s apparent, by definition, that the creatures that received “better upgrades” were more likely to survive. An “upgraded” creature is one that is better fit to survive, thus they will survive more often.

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