According to the Stanford Encyclopedia of philosophy Schopenhauer was one of the first philosophers to advocate for the idea that the universe was not something "rational" What is an "irrational" universe then? Is there a difference between a universe being beyond the grasp of human reason and saying that the universe is "irrational"? Does he mean to say that the universe can do things that are illogical such as have square triangles?

It's been years since I've read Schopenhauer, so I cannot respond with his position as such. What I am noticing is that you seem to have excluded other possibilities by assuming that if the universe is not rational it must be irrational. What about non-rational, for example? No squared circles needed!

If we posit that rationality is a capacity of human consciousness - and a mysterious thing consciousness is - what might it mean to call the universe "rational?" Are we saying it is conscious? Does the analogy to human consciousness hold sufficiently to apply to the vast universe? There might be human minds that see order and disorder and apply rational principles to their observations, but it is quite another thing to ascribe rationality to ... what? The universe is one of those concepts that is not a reality one can experience. Perhaps we can thank Schopenhauer (and his 19th century counterparts) for helping us see our anthropomorphizing for what it is.

Does this help? -bjm

I'm also no scholar of Schopenhauer, but from what I remember he's claiming that our universe is at bottom non-rational -- fundamentally arising from causes rather than from reasons. The universe isn't, on this view, irrational if that means 'capable of reasoning but bad at it' or 'containing logical inconsistencies'. I take it that Schopenhauer is rejecting a theistic or deistic view that sees reason (and not causation) as fundamental to our universe. I agree with Professor Manter that neither Schopenhauer's view nor the view he's rejecting allows for inconsistent things such as square triangles.

Can I take this opportunity to grind an axe? Advocates of a supernatural (theistic or deistic) origin of our universe often claim that only their view -- rather than metaphysical naturalism -- gives us hope of achieving a rational understanding of the universe by investigating it. They say that only if the universe was rationally intended can we hope to understand it. I think the opposite is true. If the universe arose supernaturally, rather than by means that natural science could in principle explain, then we have no hope of understanding the universe ever more deeply by investigating it scientifically: we'll eventually hit a barrier beyond which there's literally just magic, something that by definition defies naturalistic explanation (and maybe any explanation). Only if the universe is fundamentally non-supernatural -- unintended, uncreated -- can we hope to delve ever deeper into it. A bit ironically, then, a Schopenhauer-like view of the universe as fundamentally non-rational is the one that gives us the best hope of understanding it rationally.

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