An intriguing but puzzling paper from Simon DeDeo.

He begins by noting that while physics is good at generalised predictions, it fails to predict the particular. Working at the blackboard we can deduce laws governing the genesis of stars, but nothing about the specific existence of the blackboard. He sees this as a gap and for reasons that remain obscure to me he sees it as a matter of origins; the origin of society, consciousness, etc. To me, it’s about their nature; assuming it’s about origins constrains the possible answers unnecessarily to causal accounts.

Contrary to our expectations, says DeDeo, it’s relatively easy to describe everything, but hard to describe just one thing – the Frame Problem is an example where it’s the specifics that trip us up. By contrast, with the Library of Babel, Borges effortlessly gave us a description of everything. The Library of Babel is an imagined collection which contains every possible ordering of the letters of the alphabet; the extraordinary thing about it is that although it is finite, it contains every possible text – all the ones that were never written as well as all the ones that were.

We could quite easily write a computer program to find, within the library, all occurrences of the text string ‘Shakespeare’, says DeDeo; but there’s no way of finding all the texts about Shakespeare that make sense. That’s surely true. DeDeo says this is because what we’re asking for is more than just pattern matching. In particular, he says, we need self-reference. I can’t make out why he thinks that, and I’m pretty sure he’s wrong, though I might well be missing the point. To me, it seems clear that in order to identify texts that make sense, we need to consider meanings, which are not about self-reference but reference to other things. In fact, context and meaning are of the essence. One book from the Library of Babel contains all books if we are allowed to apply to it an arbitrary interpretation or encoding of our choice; equally any book is nonsense if we don’t know how to read it.

But for DeDeo this is a truth with a promising mathematical feel. We just need to elucidate the origin of self-reference, which he thinks lies in memory at least partly. The curious thing, in his eyes, is that physics only seems to require (or allow) certain levels of self-reference. We have velocity, we have acceleration, we have changes in acceleration; but models of worlds that have laws about third- or higher-order entities like changes in acceleration tend to be unstable, with runaway geometrical increases messing everything up.

So maybe we shouldn’t go there? The funny thing is, we seem to be able to sense a third-order physical entity. A change in acceleration is known as ‘jerk’ and we certainly feel jerked in some situations. I have to say I doubt this. DeDeo mentions the sudden motions of a lift, but those, like all instances of jerk, surely correspond with an acceleration? I wonder whether the concept of jerk as a distinct entity in physics isn’t redundant. For DeDeo, we perceive it through the use of memory, and this is the key to how we perceive other particularities not evident from the laws of physics. We tend to deal with coarse-grained laws, but the fine-grained detail is waiting to trip us up.

It’s not all bad news; perhaps, DeDeo speculates, there are new levels we have yet to explore…

I’m very unsure I’ve correctly understood what he’s proposing, and the fact that it seems to miss  the real point (meaning and context) might well be a sign it’s me that’s not really getting it. Any thoughts?

 

 

9 Comments

  1. 1. Peter Martin says:

    Interesting paper, thanks for pointing it out.

    I think that physics works with low level features of the the way the world works, not composite objects and their interactions. As soon as we take an interest in composite objects, the way the world changes over time depends on the pattern of these composite objects. Control of future outcomes can flow through particular distributions of their parts, and this can be more effective in predicting what will happen in the future than going down into the low level physics and then back up into the level of composite objects (even though that is the way the work may be working physically). Memory is about the pattern embodied in a composite object.

    An analogy is Conway’s Game of Life, in which the low level rules (the physics) are simple and sufficient to crank the world forwards in time, but composite objects with particular characteristics, behaviours and interactions appear to emerge; and doubtless sufficiently complex ones could hold partial representations of each other which could affect their behaviour.

    When we start to talk about meaning, or existence, we are working with pairs of composite objects, since these concepts can only be relative to the interaction between them. Something can only exist or not exist in reference to another composite object, it is not an absolute (except relative to god, if you want to go there, which I don’t!).
    Regards
    Peter M

  2. 2. Hunt says:

    An alternative to the Library of Babel would be the Brains of Babel, avoiding the interpreter/interpreted problem. While every book requires a brain to interpret it, any given text might be interpreted by some brain as any other text.

    (Note that I don’t really buy this argument at all, but others seem to love it. It seems false just by total possible information content alone. Windows XP will never be Windows 10 no matter what hardware it’s run on.)

    So “any text” reduces to the same text and different brains. But then the text is entirely irrelevant and might as well be thrown out. One flaw here is that there must at least be some symbol used by the brain keyed to the meaning of the text. The symbol might be as long as the text, and we’re back to square one.

    The reverse is not true, since any text can be interpreted (“mean”) the same thing as any other text, supposedly.

    The shorter version of all this is that brains can do without texts, but texts can’t do without brains.

  3. 3. Simon DeDeo says:

    Hello Peter—lovely. https://twitter.com/SimonDeDeo/status/927580646561800194 is a series of thoughts on your piece.

  4. 4. Peter says:

    Many thanks, Simon; reassuring to know I mostly understood you right. I’m still not sure about the role of self-reference, but I probably need to reflect further!

  5. 5. Callan S. says:

    Could you have a Darwinian tower of Babel?

    An organism responds to the various configurations of texts with physical responses, in order to perhaps survive in an environment by these responses. Sure a lot wouldn’t survive, but eventually the way the organism reacts to the ink marks would grant it some survival capacity. So the text is a solution, but without any interpretation.

  6. 6. Gary Ehlenberger says:

    The set of different images a given digital camera can take is finite, yet acts like an infinite set. I call it pseudo infinity. A simple binary bit add program will generate it (takes a very long time). A picture of you doing anything that can be photographed is in there. A more general version of the Library of Babel and easier to visualize.

  7. 7. Simon DeDeo says:

    Callan—yes, indeed. Chaitin has talked about evolution in the context of undecidability, https://www.amazon.com/Proving-Darwin-Making-Biology-Mathematical/dp/1400077982

    Gary—a very nice example. And drives home an obvious point: the vast majority the pictures in that set are will look, to us, indistinguishable from white noise. Reality and meaning are very thin and fractal sets within an incomprehensibly large system.

  8. 8. Jochen says:

    We just need to elucidate the origin of self-reference, which he thinks lies in memory at least partly.

    Reminds me of a Rilke quote (or maybe its opposite):

    “The future enters into us, in order to transform itself in us, long before it happens.”

    As for self-reference and meaning, well, I’ve kinda been trying to get that connection to work with the von Neumann replicators. It’s sort of the simplest loop of meaning: a symbol that denotes itself—Hofstadter’s ‘a mind is a pattern perceived by a mind’. Once you’ve got that, you might be able to use it to ground less trivial sorts of meaning.

  9. 9. Roberto Osorio says:

    As a physicist, I always thought the idea of “jerk” as a fabricated sensation. It’s just the sense of acceleration coupled with a memory of a previous different (usually opposite or zero) one. Our senses are consistent with the instability of worlds described by third- or higher-order dynamics. We do not really “feel jerked.” We feel a new acceleration and describe it as novel state.

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