This could maybe, possibly be true if it were possible to have complete knowledge about the (quantum) state of the universe, but that is impossible. The uncerta

This could maybe, possibly be true if it were possible to have complete knowledge about the (quantum) state of the universe, but that is impossible. The uncertainty principle isn't a hypothesis, it's not even really a theory, it's a direct mathematical consequence of the laws of quantum mechanics. I want to be clear that my point is not merely a technical one. I'm not just saying "it's technically impossible to have complete knowledge," I'm saying that it is physically, mathematically impossible. The laws of physics do not allow it. One might argue "maybe it's not possible, but if we did know the complete quantum state of the universe, the universe would be deterministic and we could predict everything," but this is equivalent to saying "if the laws of physics were different, then the universe would be deterministic." Edit: To the distinction you make between "physical" and "quantum" processes: There is no distinction. Quantum effects do diminish in magnitude with increasing size, but they never truly go away. You can predict the motion of macroscopic objects with what may seem to be an arbitrarily high degree of certainty, but in truth you can never have 100% complete knowledge of even macroscopic properties. I still disagree with your claim that the universe is deterministic in any way, even if you conveniently exclude systems for which quantum effects are substantial.