[joe-collins]

I'm at the same level of partial knowledge where I agree with you. My understanding is that everything in the universe interferes with everything else, but we assume, with some justification and empirical success, that the impact of sufficiently distant or indirect effects is negligible. That's demonstrably close to true for systems of a certain small size or complexity, but it doesn't seem remarkable to me that the assumption might fall apart with a wider perspective.