>[4] Why just one rule?
Is a specific combination of rules not itself a rule? A lot of descriptions of Conway's Game of Life describe it as multiple rules, and other places refer to its whole setup as a "rule". Rule 30 is sometimes called a "rule set". I don't think there's a strict difference between a rule set and a rule, though the simpler rule(set) the better seems to be easy to agree on.
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>(5) I would direct this last point at all TOE-heads like Wolfram and Weinstein and whoever. Why does it have to be simple? Why does it have to be elegant?
A theory with fewer free parameters is better than one with more. I think this extends to the complexity of the theory too: a theory with more rules (rule A applies to small stuff, rule B applies to big stuff, rule AB-patch applies to mediumish stuff) is worse than as a theory that explains the same stuff with fewer rules (a single rule X that naturally has A-behavior with small stuff and B-behavior with big stuff) in the same way a theory with more free parameters is worse than a theory with similar predictions and fewer free parameters.
It's Occam's Razor. Complex theories can have lots of different variants that each match the existing evidence but make different predictions in untested scenarios. Simpler theories have fewer variants that successfully match the existing evidence and tend to be more useful for making predictions, indicating that they match reality better.
>And the rule hardly runs itself. What does it run on? Great you have a generalised term-rewriting system (how completely un-novel). "What rewrites the terms?* How is this not the first question you ask yourself?
Is that not an obstacle for any theory? Tons of theories are meant to model what we see, without presuming some underlying mechanism. Newton came up with a theory of gravitation that modeled how objects tend to pull each other in without any idea of why nature chose for that to happen.
Even if the idea that not explaining what executes the rule of reality is a problem, then a simpler theory with fewer rules is obviously better because there's fewer unexplained rules.
>[5] Hey, why not just say: “You know that "it from bit" idea? We have a hunch that term rewriting hypergraphs is the way to go. These are our explorations. We've encountered stuff that echoes contemporary physics.” Why not write the intro like that? Not grandiose enough for you?
Personally, I found their intro to have a lot more background detail and motivation explained. Is your primary objection really that they were too grand for a few paragraphs?
>(1) Given that we know that any sufficiently powerful computing system can emulate any another what motivates your choosing this particular computational system and model?
Any system capable of having relativity and QM-like effects emerge out of it as described is interesting enough to study, even if it did end up having defects that meant it couldn't be a good model of reality overall.
I feel like you're treating this as if he's asking everyone to commit themselves fully to this model instead of to explore it.
>(5) I would direct this last point at all TOE-heads like Wolfram and Weinstein and whoever. Why does it have to be simple? Why does it have to be elegant? Why is it always encoded in the formal systems you happen to play around with (geometry for Weinstein, term-rewriting systems / cellular automata for Wolfram).
Presumably they chose those systems to play around to begin with because they believe those systems were promising.