Comment by voidhorse | Hacker News Reader

Comment by voidhorse | Hacker News Reader

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Yeah, but my point is that "information" is not really a substantive concept. It is an abstraction. It is a useful technical tool. For the record, I am a nominalist when it comes to mathematics. Thinking that information is some "real thing" with meaning independent of theoretical context and interpreters is a definitely Platonisist perspective (the idea that our mathematical representations are not merely useful technical models but that they correspond to some real substantive elements of the real).

Claiming that "information" is the underlying basis of the real is the same as effectively saying that "stuff" is the underlying basis of existence. It's essentially Platonism. It is not informative. What is informative is the operational use of the mathematical concept of information as defined by Shannon to understand real things or to structure theories. But this is a very different thing than identifying a substance that exists, independently of us in the universe. This "making real" of what is ultimately a mathematical abstraction is precisely reification.

This stance is very tempting because it appears so straightforward and no-nonsense. But there are issues which undermine it in my mind. Because, at a closer inspection, it itself doesn't seem informative, in the end coming down to a question of semantics, i.e. how we define the word "reality". Which then determines whether it encompasses the realm of mathematics or not. I wonder what definition you favor, but the language you use points towards something like "the totality of all things" or "everything that's made from a physical substance". Yet platonists and other realists wouldn't argue that numbers are made from a substance as you imply.

Physical reality is a slippery thing. Yes, at the level of our daily life it all seems very solid and obvious, but inspecting that foundation revealed a bewildering world of relativity and uncertainty. And one of the most intriguing ways out of this bewilderment seems to be the "it from bit" trend in physics, which makes information the fundamental reality.

I personally don't feel the need to tie the notion of reality to physical phenomena. I prefer something more along the lines of Philip K. Dick's "reality is that which doesn't go away when you stop believing in it", or, as you put it, "something which exists independently of us". The fact that there are an infinite number of primes, is such a fact. Surely any alien civilization would know this fact. Maths doesn't go away when we look away, and neither does the notion of computation. Sure, Turing machines are a human construct, and there can be others as well. But the Church-Turing thesis speaks about how these constructs all ultimately describe the same underlying reality.

"it from bit" is just "shut up and calculate", positivism. There are no bits in physics, and no boolean phenomena.

Let me try again. We use miles to measure distance. Hopefully you agree with me that, miles, being a system of measurement to express relationships of distance, have no ontological existence themselves. I would find it completely bizarre, for example, for someone to argue passionately that, "no miles are the real deal and something that exists in the universe and meters are a fabrication". Distance surely is a real phenomenon, but "miles" are a system of expression.

Bits and information are the same thing. They are a system of measurement to express relationships of difference. Difference and change as physical phenomena exist, but bits do not.

So, yes, pointing out that the limits of computation give us some useful facts about the way things change in reality is a useful perspective. Going further and saying something like "computation is the basis of reality" or similar extremes is too reductive and too abstract to really be a useful piece of knowledge in my view. Finally, to claim that information is somehow the important fundament of existence is patently absurd to me, since it would've similar to arguing that miles have some very special epistemic and ontological status.

That's just it though.

Yes, separating symbols/descriptions from the physics is a common conflation, rightfully avoided and called out here, but I think you might be overcorrecting unconflating the concepts too much.

Quantum information is strange precisely because the theory treats information-like relationships as physically consequential.

Entanglement, path dependent stuff, cloning theorum, black hole information paradox... There are so many areas you run into where its information-centric descriptions appear to fit unreasonably well.

Again, I'm not saying the symbolic representation is "real" per se (not saying it's not either, I simply don't know what it is).

I agree bits are just nomenclature, but I don't agree that "bits" and "information" are the same thing. Like distance, "information" has a deeper and general architecture to it.

And it's also weirdly physical in places that I wouldn't expect it to be, for reasons I simply don't understand at the moment.

I don't know enough about the quantum level to really understand whether or not that would change my view of things.

From Shannon's theory, it's abundantly clear that "information" is just a mathematical description of difference and expectation. I can frame anything as information. If I know who my parents are, a statement about who they are is not informative to me because it constitutes no difference. The entropy and expectation/surprise is low. If someone approaches me with a compelling argument that no, actually, my parents are not my parents I was adopted and my real parents are so and so, this is informative. The entropy is high.

Crucially, this all depends on me my personal history, and my status as an observer. It is in this sense that I find information to be a communications concept (which is how it started!) or semiotic concept more than a useful abstraction for organizing our knowledge about other parts of reality. Yes, the abstraction might still be useful if e.g. quanta end up behaving in some way according to shannon's laws, that is interesting, but to me uh at is not an argument that turns information into some kind of "universal substrate" of the real—it is just a surprising applicability of laws in one domain to another. Is it surprising that empirical data fit the model? Maybe. Idk, lots of empirical data can be made to fit all kinds of models (there are ways in which hI can reasonably take a Newtonian view of various aspects of my life and the data generally won't contravene the laws).

> From Shannon's theory, it's abundantly clear that "information" is just a mathematical description

That's a very narrow and technical definition of information. It's what people refer to by the word when they discuss things like: communication, medium, surprise, compression, etc. in a technical context. Otherwise one should refer to the dictionary definition, so we don't end up talking past each other.

If you'd like to get a better intuitive sense of what "it from bit" points at, check out David Deutsch's Constructor Theory and the Stephen Wolfram Physics Project. Also, Bernardo Kastrup, on the philosophy front.

> Finally, to claim that information is somehow the important fundament of existence is patently absurd to me, since it would've similar to arguing that miles have some very special epistemic and ontological status.

As the sibling comment says, no, it is like arguing that distance/space/extension has a special ontological status — which it does. "It from bit" is just using the word "bit" for the rhyme, the theory is quite profound and compelling, at least to me.

Then there's also Max Tegmark's "Mathematical Universe" idea, which makes the symbolic world the fundamental one. It goes a bit far for my taste, but it has its own internal coherence.

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