Third in series “20 Atheist answers to questions they supposedly can’t”
3. Why is the universe rational?
Short answer: Why shouldn’t it be? Why does God make us think it should be?
Long answer: The argument implied by this question is something like this. It is very surprising that the universe is tractable to reason is naturalism/Atheism is true. Not so if God exists: for he would want to create a universe that the people inside it could understand. So that we find ourselves in a tractable universe is evidence for the existence of God.
Yet both of these seem pretty dodgy. For the first part, it seems Atheist can give a story in reverse of why we can work out the universe. If there are known regularities/’laws of nature’, there are plausibly survival advantages in working these out, and so a selective pressure towards brains which can do this. So our minds are sculpted by natural selection to make sense of the universe, and not the other way around (indeed, this would seem to make more sense of how various bits of our best science are very complicated and counter-intuitive – if God wanted us to understand the universe, why not give us perfect understanding?)
The next reply is something like “Okay, but that only works if the universe has known regularities, and what are the chances of getting a rational universe just by chance?” Yet this recapitulates the same problems facing the fine-tuning argument. We have no way to work out the relative measures of ‘rational’ and ‘irrational’ universes on naturalism (for all anyone knows it is a brute fact or logical necessity nature cannot be chaotic, etc). So see there.
The other problem is it isn’t clear that Theism predicts a rational universe all that well. Sure, in our rational universe we can produce an explanation now as to why God would want a rational universe for our understanding etc. Yet it seems likely that if we really did live in a universe completely obscure to our reason, we wouldn’t have too much of a problem concocting an explanation as to why God would want this universe instead (“It’s all about how mysterious the ways of God are”, etc. etc.) Absent a non post-hoc explanation of what universe God would expect prior to helpful knowledge about what universe we are actually in, this doesn’t seem that persuasive.