Information is the new Aristotelianism (and Dawkins is a hylomorphist)

UniverseMath_m_0131by John Wilkins

“In seeking tales and informations.” [Henry VIII, Act V, scene 3]

For some time now [1] I have had problems with the notion of information. Not, please note, with this or that piece of information, but with the notion itself, especially in the natural sciences. In this age of computers and internets, we have taken to mistaking the thing described for the thing itself, and treat information as a property out there in the world, not a representation in our heads and language.

Let me set the scene. Back when Dawkins wrote about biology, he proposed the idea that genes were a special case of what he called the Replicator:

“A replicator may be defined as any entity in the universe of which copies are made.” [2]

Notice the word “copy.” I can copy things in a number of ways, from imitation to tracing, but Dawkins has a particular sense in mind, which he explored in an especially purple prose passage in The Blind Watchmaker (1986):

“It is raining DNA outside. … [downy seeds from willow trees] The cotton wool is mostly made of cellulose, and it dwarfs the tiny capsule that contains the DNA, the genetic information. The DNA content must be a small proportion of the total, so why did I say that it was raining DNA rather than cellulose? The answer is that it is the DNA that matters… whose coded characters spell out specific instructions for building willow trees… It is raining instructions out there, it’s raining programs; it’s raining tree-growing, fluff spreading, algorithms. That is not a metaphor, it is the plain truth. It couldn’t be any plainer if it were raining floppy disks.” (Chapter 5, p 111)

DNA, and the replicators they are a special case of, are information. This is not a metaphor. Similarly, physicists will occasionally assert the same claim about physical things. “The physical world is just a mathematical construct, and things like electrons have only mathematical properties,” says Max Tegmark, a physicist at MIT [3]:

“… all the properties that electrons have are purely mathematical. It’s just a list of numbers. So in that sense, an electron is a purely mathematical object. In fact, there’s no evidence right now that there’s anything at all in our universe that is not mathematical.”

We get the “it” from “bit” [4]. Some mischievous philosophers [5] have even suggested that we do, actually, live in the Matrix, although what the Matrix lives in is unclear.

So, why am I unhappy? Is this wrong? I think it is.

To get at this I need to hit you with a little bit of natural philosophy from the Greeks, in particular from Plato and Aristotle. Plato famously proposed that the real world was the world of Forms, or ideas (the Greek word he used was ideai, from the root eidos, meaning appearance, something seen). Forms were more real than what you see around you. A physical circle is at best an imperfect instantiation of the real circle, which exists nowhere in physical form.

Aristotle, in contrast, explained the physical things in the world by supposing that they had matter, which filled space and gave weight (made from several admixtures of the four elements, two light and two heavy) which the scholastics called substance (substantia, meaning that which stands under), and form, the structure and mathematical properties of a thing. This matter/form dualism is called hylomorphism, from the two Greek words hule, meaning stuff (it originally meant “wood”) and morphe, or form. Hylomorphism was intended to be an alternative view to atomistic materialism, which had become a widely held (and generally atheistical) view in his day. Epicurus had an entire philosophical school based upon the older Democritan atomism [6].

Now hylomorphism was roundly demolished as a scientific hypothesis when Daltonian elements were named and investigated in the nineteenth century. By 1900, terms like “substance” (for matter that is propertyless apart from mass and extension in space) and “form” had taken on a largely philosophical sense that differed extensively from Aristotle’s own views. Instead, an increasingly elaborate atomism had won the day, far beyond anything Epicurus or Democritus had posited. The properties of things, including their mass and filling of space, were the result of fields in space-time.

And yet, a kind of hylomorphism remained, even in science. Biologists argued that form determined many properties of organisms in ways that could not be reduced to their parts, and this kind of thinking was co-opted by the molecular biologists and geneticists of the 1950s, especially since around that time, computers were getting going and information was a hot topic (it had not been much prior to that period). Thus, we get the “Central Dogma” in genetics:

“The central dogma of molecular biology deals with the detailed residue-by-residue transfer of sequential information. It states that such information cannot be transferred back from protein to either protein or nucleic acid.” [7]

Read physically, this means only that the structure of the DNA molecule is not reproduced from the structure of proteins, a perfectly reasonable account of the molecular processes. But because Crick used the word “information,” some scientists, including Dawkins, took this to mean genes are informational entities that “code” for organismic traits from the molecular level up to the entire organism and even beyond.

Likewise, physicists like Tegmark, Wheeler and so on, who say that the physical world is “just” information can be read as saying that there is physical structure in the world. This is harmless.

But this is not how “information” is interpreted usually. Instead, we get the idea that information is itself a kind of universal property that underlies all physical things. Information, which is the modern equivalent of Aristotle’s morphe, has become the equivalent also of Aristotle’s hule. And this is where I part company.

When scientists talk about the information content or the informational entropy of something, they can mean several things. They can mean the entropy of the string of characters that are used to measure or describe that thing, like a mathematical description of a process, or a sequence of symbols like the G, T, A, and C, of DNA. But DNA is not composed of G, T, A, or C. It is composed of molecules, nucleotides, that bear the symbols as names, and they have properties that mean that occasionally they do not follow the mathematical or semantic descriptions of these names. For example, there is a “fifth nucleotide,” 5-methyldeoxycytidine (5-mC), which can pair up in 5′-CG-3′ dinucleotide positions. 5-mC is a methylated molecule, a class of chemicals that modify the expression of the DNA. The informational entropy (or information content) of a sequence is therefore just a measure of how the DNA is represented. 5-mC can even breech the Central Dogma.

The point here is that the representation abstracts away from the physical properties of the molecules. Measures of the informational entropy are therefore actually measures of the abstract representations, not the things themselves. But suppose we had a simulation or representation of the things right down to the level of quarks (if that were physically possible): would the informational entropy of the objects be identical to the physical properties? Would we have the physical informational entropy of the objects? I’ll get back to that. First I’d like to consider some of the other meanings of “information” in science.

Another one is the semantic meaning: what one thing (e.g., a gene) represents (e.g., the phenotype). This is the “information as signal” view, based loosely or strictly on Shannon’s Communication Theory account. One thing “refers” to another (in Shannon’s theory, the received message “refers” to the sent message). This, as Shannon noted, is not a theory of the content of a signal. After all, a gene sequence does not represent the phenotype by describing it. A similar view is Wiener’s notion of information as control, the cybernetic account. It is very hard to think of these kinds of information underpinning the physicists’ view above. Here, the properties are just informational, or as they put it, mathematical. Program-style accounts of genes are in this class.

A third kind of information is the information, or rather the accuracy, of measurements. This is called “Fisher information” after its originator. It is roughly the point on a curve of measurements where the second derivative is zero, or where the error curve is flat. This cannot apply to either physical or biological information, as it is a measure of how well and closely we can measure a physical system. Ironically, it is in my view the only actual physical sense of information, since it requires a physical state to be measured, and a physical system to do the measuring.

So let us get back to the physicists’ claim that the universe is just information. I have argued before [see note 1] that if an electron has mathematical properties, this is not the same thing as saying that the electron is just a mathematical object. An analogy might make this clear. Suppose I program my computer as an orrery, a simulation of the solar system. If I do this, the computer represents the mass and physical constants as numbers, and processes them according to the mathematical equations of physics. But that solar system in my computer doesn’t have the mass of a real solar system (luckily for me, and everyone else on earth). Instead it has an abstract mass, and the ways the abstract sun and planets interact is, well, abstract. A mathematical description of a system like the solar system is abstract. Apart from instances of that description in physical objects like heads, paper or computers, it exists nowhere in space or time. Consequently, abstract properties do not cause anything in the physical world.

Moreover, the abstractions must leave something out. As the genetic A, C, G, and T leave out the actual physical properties of adenine, cytosine, guanine, and thymine, which can occasionally do things the symbols cannot, even the most well specified and detailed representation of a thing will leave out properties and capacities we are not interested in representing, and so they will sometimes deviate in their representation from the actual things. And if we have the fundamental objects (quantum fields?) of the universe, we could not compute the system without first constructing a computer capable of dealing with the whole system, and for a universe, that would have to be a universe-as-computer.

When physicists or philosophers say that we are living in the Matrix, or equivalent statements like the properties of atomic and subatomic objects are merely mathematical, they make a classical mistake: they are mistaking the representation of a thing for the thing. The late medieval scholastics like Lombard knew this error and named it long before Saussure: the sign is not the thing signified. The word is not the world. If we are living in the Matrix, what does the Matrix live in? We know of no information processing system that is not, itself, physical.

This is the New Hylomorphism. Information is, as a commentator on Antievolution.org said [8], seen by Intelligent Design proponents as a kind of caloric or phlogiston. But it isn’t. It causes nothing at all. An abstraction cannot cause a physical process, and to think otherwise is a category error, unfortunately common among theoreticians as well as Intelligent Designists.

The notion of “information” in genetics is an honorary one. It can only mean causal specificity, not anything involving “real” information (on this, see Griffiths and Stotz’ Genetics and Philosophy [9]). And since we have no real reason to adopt hylomorphist views of the real world any more (atomism, or its linear descendants, won the battle), one has to wonder why some scientists and some philosophers think it necessary to reintroduce form as information. Replicators are not informational objects; they are molecules and systems of molecules [10, 11]. For this reason I much prefer the notion of a “reproducer” [12], which is a physical entity (or class of entities).

It is time that we stopped making this mistake in science. It is time to give up on hylomorphisms, old or new. In the end, these metaphors (and they are metaphors) only mislead us. I think that is enough about information from me [too much information].

_____

John Wilkins is a Melbourne-based, University of Sydney and University of Melb affiliated historian and philosopher of science, especially biology. He blogs at Evolving Thoughts. He wrote Species: A History of the Idea, University of California Press, 2009. Most recently, he is the co-author of The Nature of Classification.

[1] See: Is information essential for life? No.Why not information?Mechanism, informationism and OckhamismMore of me in Spanish, and information againInformation and metaphysicsInformational caloric; and Descartes before the horse — does information exist?

[2] Replicators and Vehicles, by R. Dawkins, 1982.

[3] Do We Live Inside a Mathematical Equation?, Science, 16 February 2013.

[4] Digital physics, Wikipedia.

[5] The Matrix as Metaphysics, by D.J Chalmers.

[6] Epicurus, by D. Konstan, Stanford Encyclopedia of Philosophy.

[7] Crick, Francis H.C. 1958. On Protein Synthesis. Symp. Soc. Exp. Biol. XII, 139-163.

[8] See here.

[9] Griffiths, Paul, and Karola Stotz. 2013. Genetics and Philosophy: An Introduction. Cambridge University Press.

[10] Griesemer, J.R. (2005) “The informational gene and the substantial body: on the generalization of evolutionary theory by abstraction.” In Idealization XII: Correcting the Model. Idealization and Abstraction in the Sciences, edited by Martin R. Jones and Nancy Cartwright, 59-115. Rodopi Publishers.

[11] Waters, K. (2000) “Molecules Made Biological.” Revue Internationale de Philosophie 54:539-564.

[12] Replication and Reproduction, by J.S. Wilkins, Stanford Encyclopedia of Philosophy.

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61 replies

  1. I have managed to navigate the world more or less successfully without making any assumptions about its reality for at least 20 years now. How would any assumption about reality increase my ability to do so?

    That I find hard to believe. No assumptions? I think you are making assumptions about not making assumptions that are unwarranted.

  2. My point was to contrast a simulation with an assembly. For example, we can run a model of a human heart in a computer (a simulation), but apparently we are close to having a 3D printer that can print out that model as a working heart (an assembly).

    Maybe someday we could print out the model of a new universe with a different physics that comes out on the other side of a black hole. The sentient beings (they would not be living in a simulation, but an assembly) that may come about may not ever know.

  3. Some accounts of physical causation rely upon a “conserved quantity” account. One can recast “preserved information” as a “conserved [physical] quantity” without loss. I prefer that account, as you may gather.

    As to maps becoming, I have in mind Lewis Carroll’s Sylvie and Bruno Concluded:

    “Mein Herr looked so thoroughly bewildered that I thought it best to change the subject. “What a useful thing a pocket-map is!” I remarked.

    “That’s another thing we’ve learned from your Nation,” said Mein Herr, “map-making. But we’ve carried it much further than you. What do you consider the largest map that would be really useful?”

    “About six inches to the mile.”

    ” Only six inches ! ” exclaimed Mein Herr. “We very soon got to six yards to the mile. Then we tried a hundred yards to the mile. And then came the grandest idea of all ! We actually made a map of the country, on the scale of a mile to the mile !”

    “Have you used it much?” I enquired.

    “It has never been spread out, yet,” said Mein Herr: “the farmers objected: they said it would cover the whole country, and shut out the sunlight ! So we now use the country itself, as its own map, and I assure you it does
    nearly as well.”

  4. Hi John,

    I fail to see how casting information as a conserved physical quantity makes it less real. Energy and momentum are also conserved physical quantities which some would regard as real.

    Thanks for reminding me of Sylvie and Bruno’s map. I had read that many years ago. Lewis Carroll is insightful and thought-provoking as always.

    I remain confused as to whether you think the point about maps and territories has been settled or not. Again, my view is that maps can be identical to the territories if both are mathematical objects, and as such it is wrong to claim that people who suspect the universe may be a mathematical object are simply confusing the map for the territory.

    Whether they are right or wrong, it seems clear to me that there is more than simple muddled thinking going on and it doesn’t do them justice to dismiss them so easily with aphorisms such as “the sign is not the thing signified”.

    (The sign is the signified if what you are trying to signify is the sign itself, e.g. the symbol ‘+’ in this example both signifies and is the symbol ‘+’.)

  5. Hi Michael,

    Please re-read, I didn’t say I made no assumptions.

    I said I made no assumptions about the world’s reality.

  6. I was going to comment merely that I think the Central Dogma is not that all information flows from DNA to, ultimately, proteins. I think that it says that there is no process that the amino acid order of any given protein is instantiated in a novel DNA strand. And I think the distinction makes a great deal of difference in research in abiogenesis and also in understanding tRNAs.

    However, it seems that a recurring controversy over the ambiguity of skeptical epistemology has, well, recurred. So far as living in a simulation goes, I’m pretty sure that there are multiple issues regarding computability, computation time, decidability of algorithms budgeting processing time, problems with chaotic determinism. Just one example: How does the simulation program input a value for the effect of a butterfly flapping its wings in Brazil? How do you round off and where does the hurricane blow after that? Oh, I admit it, I liked, here’s a second example: How do you simulate interstellar photons that might be detected by a Hanbury Twiss Brown interferometer?

    I don’t think there’s any sensible way to say that the universe can be simulated. All this chatter about Chaitin restraints seem to me to make it perfectly clear that talk about computing a simulation is nonsense. Again, given the foundational issues in mathematics, I don’t know how mathematical Platonism can hope to claim to be mathematical knowledge. Mathematical Platonism seems to be self-refuting, relying solely upon a fixed determination that only the unchanging logically necessary a priori counts as knowledge. Undecidability and incompleteness would leave blank spots in the simulation. I am amenable to trying to understand a brief sketch of how they don’t? The thing is, i don’t think the most unregenerate mathematical Platonist has even made the slightest effort to do that.

    And further, doesn’t Occam’s Razor, which if I understand correctly was always meant to apply to Forms, which means that any Platonism needs to explain which abstract objects are relevant in any given instantiation? Which is to say, we need some rule to determine which Forms are the minimum needed to “explain” whatever it is the philosopher is trying to explain about the real world. The thing there is, is that among other implications of Turing’s work, is the conclusion that all the Platonic forms can be abstracted as programs. That brings back all those pesky problems with decidability and computing time, meaning that the Platonic Forms can’t calculate the world either. But there erupts a kind of War in (Platonic) Heaven, in which the mathematical Forms of Whiteness and Horseness and Hoofiness and Animal Metabolism struggle eternally to “explain” the white horse.

    (If I have offended anyone by treating Occam’s Razor as a critique of Forms instead of a heuristic guide for empirical investigation and thereby desecrated his spirit, my apologies.)

  7. It’s a bit from an it and the rest is useless shit,
    in terms of what can be described by bits for its.
    But all that useless shit,
    that’s not described by bits,
    nonetheless
    exists.

  8. Disagreeable, I do not think making information (as structure in the world) a conserved quantity makes it less real, but it does tend to undercut the semantic and syntactic elements of physical information. Given that there is structure in the mind-independent world, call it information if you like, but do nto import the semantic and syntactic connotations, which is what I am objecting to. This is a form of reification fallacy.

  9. There once was a physicist who thought it
    Was formed from a collation of bit
    When his computer crashed
    He went and got smashed
    And admitted he was full of excrement.

  10. You’re using ‘computer’ purely based on it’s meaning, the article is using it as the label of a specific type of machine, one which doens’t operate in the same way as biological entities do.

  11. John, thanks for this article. Your writing is clear and confident – exactly what I’d like to read more of.

    DisagreeableMe, it seems to me you have two main points in favor of your view – first, that mathematics is sufficient to account for reality, and so positing some other stuff on top of it is unreasonable. This begs the question, I *think*: maths is sufficient to account for our best description of reality, but there’s no way to know that it can account for reality itself. Better to say “I don’t know”? And second, that math is independent of minds (2 is 2 no matter where it shows up, even if there are no minds to think about it; a^2 + b^2 = c^2; etc.). Is it the same with logic, e.g., A = A? I think A = A is dependent on minds, even though I also think that any mind worthy of the name would have to formulate and use A = A. So, to me, it’s not inconsistent to say the same about math (that math is dependent on minds, and that all minds would create the same math).

    Robin Herbert, you wrote “I would say that the concrete realisation is, in itself, the abstraction having an effect. You can’t have a concrete realisation of an abstract thing unless you have that abstract thing.” I think this is directly begging the question. One might as easily contend that you can’t abstract from something without first having the concrete referent, and that abstractions supervene on their representations, not vice versa.

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