Today's post, Reductionism was originally published on 16 March 2008. A summary (taken from the LW wiki):
We build models of the universe that have many different levels of description. But so far as anyone has been able to determine, the universe itself has only the single level of fundamental physics - reality doesn't explicitly compute protons, only quarks.
Discuss the post here (rather than in the comments to the original post).
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So? What query are you trying to answer?
Are you asking whether we ought to study and understand reductionism? Answer: yes, if we don't get reductionism, we might miss that uploads, etc. are possible.
Are you saying it may not be worth it to learn all the low-level detail, because our higher abstractions aren't all that leaky. Answer: agree for most things, but some require the lower stuff.
Why are you bringing this up?
I thought I had clearly explained it in my original top-level comment: the underlying structure is irrelevant for the entities a few levels removed.
And if it did, it wouldn't matter for atomic physics and up.