Yeah, I think the idea of Laplace's Demon is mostly just useful to make a philosophical argument about whether or not the universe is deterministic, and it's implication on free will.
I dunno, I wonder what Laplace would have made of the argument over the meaning of wavefunction collapse. It took me a very long time to come to terms with the idea of a non-deterministic universe.
That's peculiar. Most people probably struggle more with the idea of a deterministic universe, as it'd leave no room for free will, which would make everything kind of meaningless.
I'm also more in the camp of "quantum effects making the universe non-determinstic." It's a nicer way to live.
I've evolved over the years from "determinism implies no free will" to roughly being a compatibilist (https://en.wikipedia.org/wiki/Compatibilism, see also Daniel Dennett). I don't particularly spend much time thinking that (for example) a nondeterministic universe is required for free will. I do think from an objective sense the universe is "meaningless", but that as humans with agency we can make our own meaning.
However, most importantly, we simply have no experimental data around any of this for me to decide. Instead I enjoy my subjective life with apparent free will, regardless of how the machinery of the actual implementation works.
It’s interesting that many things are deterministic to human-relevant time/length scales. If the small stuff is non-deterministic, it’s interesting that large ensembles of them are quite deterministic.
