“post-modernism”, physics-style

The ubiquitous use of “post-modernist” as an insult meant to describe some sort of uber-relativistic, solipsistic mental-masturbation has always bugged me. Post-modernism was a very important development that deconstructed the illusion of humans (or “scientists” or “men”, depending on the topic) as objective observers of reality. It posited humans as interpreters of reality, who constructed models, symbols, etc.to make a counter-intuitive reality comprehensive to brains that never had any “reason” to evolve the ability to do so. And yet, people sneer at post-modernism and constructivism (the idea that reality is constructed by people) as some sort of wooey, New Agey “everyone can have their own reality and their own facts” sort of BS.

Well, imagine my glee when, while reading an article in Skeptic about Stephen Hawking’s 2010 book The Grand Design, I come upon a discussion of Hawking’s “Other Controversial Theory”: Model-Dependent Realism.
The article in Skeptic explained MDR in the terms very similar to the ones the social sciences have been using for years (but with more neurologyscience*), and the more I read about it, the more it seems to be the very same thing. But this time, it comes from a source not so easily dismissed by nerd-snobbery: the world’s most famous physicist**. A relevant quote from the book:

[Model-dependent realism] is based on the idea that our brains interpret the input from our sensory organs by making a model of the world. When such a model is successful at explaining events, we tend to attribute to it, and to the elements and concepts that constitute it, the quality of reality or absolute truth. There is no picture- or theory-independent concept of reality. Instead we will adopt a view that we will call model-dependent realism: the idea that a physical theory or world picture is a model (generally of a mathematical nature) and a set of rules that connect the elements of the model to observations. This provides a framework with which to interpret modern science. According to model-dependent realism, it is pointless to ask whether a model is real, only whether it agrees with observation. If there are two models that both agree with observation … then one cannot say that one is more real than another. One can use whichever model is more convenient in the situation under consideration. It might be that to describe the universe, we have to employ different theories in different situations. Each theory may have its own version of reality, but according to model-dependent realism, that is acceptable so long as the theories agree in their predictions whenever they overlap, that is, whenever they can both be applied.
According to the idea of model-dependent realism …, our brains interpret the input from our sensory organs by making a model of the outside world. We form mental concepts of our home, trees, other people, the electricity that flows from wall sockets, atoms, molecules, and other universes. These mental concepts are the only reality we can know. There is no model-independent test of reality. It follows that a well-constructed model creates a reality of its own.

source

So: I’m going to have to read that book now, just to make sure I’m not entirely deluding myself about this (wouldn’t want to end up like those morons who think relativity and quantum physics “are what Eastern religions have been saying for millenia”), and if it turns out to be that MDR really is a physicy version of constructivism/post-modernism, next time someone sneers at those concepts because they’re primarily used in the social sciences (and, *gasp* the arts and humanities), I might have to link them to a discussion on MDR and/or suggest the book to them.
– – – – – – – – – – – – – – – –

*dum… dee… dum…
**Yes, I’m fully aware I’m making an appeal to authority. However, nerd-snobbery is an argumentum ad hominem, and I find that, in non-formal discussions, those two cancel each other out nicely. So, to get those who commit the ad hom against constructivism to get past their mistake, I present them with an authority their tribalist brains might be willing to take seriously. In terms of intellectually honest debate, this might be cheating a bit, but fuck it: if it gets the morons to pay attention to such important concepts, it might be worth it.

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18 comments on ““post-modernism”, physics-style

  1. trinioler says:

    JadeHawk, the problem with post-modernism and all the other associated stuff most people in physics and that turn their nose up on.. is that it gets applied to things that make no sense.

    My art professor and boss told me with obvious glee and superiority about “post-modern programming”. Leaving aside the discussion that ended up concluding/explaining that civilization can be a verb(not civilizing, but civilization… I think they had meant to say civilization is an action, not a thing, something that is continually done by everyone that is part of that action), it turns out pomo programming was about not coding anything that had already been made, basically using other pieces of code to make new ones, rather than writing from scratch.

    The only issue… THIS HAS BEEN PART OF PROGRAMMING SINCE FOREVER. ITS CALLED MODULES, CODE REUSE, AND LIBRARIES. AUGHHHHHHHHHH9876897687%^*&%*&%&*$$&.

    Yeah. If they didn’t have such glee and smugness when applying their terms to stuff like physics and programming, and thinking it was something new, people like me wouldn’t dismiss it so much.

    It strikes me that positivism is MDR, at its heart. Positivism holds that we can only have models of the universe, and not the universe itself. The models are not the universe, but they can be useful and predict stuff. Too many people mistake the model for the reality, and so make conceptual mistakes.

  2. Jadehawk says:

    I can’t help the existence of idiots. The phenomenon I labeled “physicist-disease” (the black-and-white thinking that claims that either something is isolatable and repeatedly demonstrable in an experiment, or we can’t know anything at all about it) doesn’t invalidate empiricism, either.

    It’s one thing to sneer at the abuse of something, and another to sneer at a concept because idiots misuse it or extend its use where it doesn’t belong.

  3. Jadehawk says:

    oh and also, I think I find the revised positivism of Popper to be more useful: Post-positivism

  4. Martin says:

    Wait, what did I do ???

  5. Jadehawk says:

    nothing. you’ll notice that I wrote “neurology” where “neuroscience” was supposed to go. Your last post noted the difference, so I corrected, with a link to why I corrected it the way I did. I’m making fun of myself for screwing it up.

  6. Martin says:

    Oh, ok lol….That’s what I get for writing drunken rants late at night…

  7. Martin says:

    Oh, btw, I got suspended from G+ hahaha…..

  8. David Marjanović says:

    Martin, how did you get suspended from G+?

    =======================

    Postpositivism! I didn’t know that word! I’d have so loved to slap it about Kristoff’s ears in the Pharyngula thread yesterday that he turned into “y’all (and PZ in particular) don’t know any sophisticated philosophy, you’re no better than a cult”!

    =======================

    Hawking, not Hawkins. :-)

    =======================

    Huh. So neurology is only that subdiscipline of medicine. The things I learn… I guess that’s where the German term Neurobiologie, which is on its face stupidly redundant, comes from; it means “neuroscience” as far as I can tell. (I had a course in it; it’s compulsory for molecular biology students in Vienna.)

    Post-modernism was a very important development that deconstructed the illusion of humans (or “scientists” or “men”, depending on the topic) as objective observers of reality. It posited humans as interpreters of reality, who constructed models, symbols, etc.to make a counter-intuitive reality comprehensive to brains that never had any “reason” to evolve the ability to do so. And yet, people sneer at post-modernism and constructivism (the idea that reality is constructed by people) as some sort of wooey, New Agey “everyone can have their own reality and their own facts” sort of BS.

    I can see 4 reasons why postmodernism is so despised by physicists in particular and scientists in general:

    1) I didn’t know model-dependent realism even had a name. I thought it had been uttermost basic science theory for a long time now. To pull examples from physics, everyone knows quantum theory and relativity contradict each other, and both contradict some observations that the other explains, so both of them have to be wrong somehow,, and I can’t see what I’m fucking typing because the e-mail/name/URL fields don’t move while the comment window changes its size and hiand hides again what I write every time I hit a key, …aah, now the fields went down. This seems to be a WordPress-wide problem. — So, physicists know full well that their best theories, the predictions of which agree with the observations to 17 places behind the comma, are wring, but they just live with it. Indeed, they use Newton’s clearly wrong physics whenever they can get away with it. And then, several decades later, the philosophers or even literature critics come along, tell them “ur doin it rong” based on a 19th-century caricature, and tell them they should be doing exactly what they’re already doing?

    2) The postmodernists wrote in the jargon of literature criticism. They even used it where it was utterly unnecessary. Worst of all, there’s even some evidence that at least some of them used as much jargon as possible in order to appear more credible!

    3) Independently of the newage that immediately got deposited on top of it and seeped into it, some postmodernists do seem to have said that everyone can have their own reality and their own facts. Remember, Sokal’s hoax which flat-out said so was published.

    4) The fact that Sokal’s hoax was published was interpreted as evidence that pomo doesn’t have any substance and consists of jargon only, as exemplified by the pomo generator. Quelle surprise. I can’t find the xkcd comic on how long you can fake being a physicist/linguist/whatever/postmodernist literature critic without being found out…

    For at least the biologists, there’s evolutionary epistemology, which covers the part about our brains not having evolved to be the sense organs for truth that Plantinga wants and science having to work around this as far as possible. Admittedly it’s not much older than postmodernism, but still it meant that postmodernism wasn’t anything new.

    And here’s one for the linguists: Julia Kristeva wrote a textbook on linguistics that ignores half of linguistics and gets the rest wrong because she used very few sources, none from later than 1957. Somebody must have interpreted that as “postmodernists don’t know what they’re talking about”. Explanation about 2/3 down this page (comment from July 15, 2:16 pm).

    Anyway. If Trinioler is right and postmodernism is just model-dependent realism with different jargon, it’s not something bad, but what good is it really?

  9. David Marjanović says:

    (I left “wring” stand because it’s inherently funny. I note that the double space before or behind “but” was eliminated.)

  10. Alex says:

    Hi there,

    That is a very interesting topic. What you describe as model-dependent realism is very close to what I have increasingly employed as my modus operandi the longer I have been thinking about physics and science in general. I feel very strongly that departing from it is what opens the flood doors of nonsense.

    For example, the question “what is an electron” can be answered best in the framework of a theory, by stating the theory, making sure it fits well to observations, and then reference the object “electron” in the theory. The only alternatives I can think of consist of collecting phenomena and then saying “whatever is behind this set of phenomena here, I call electron”, and those are much inferior. Talking about whether electrons are real for me leads directly to nonsense.

    Two minor things I don’t agree with

    You talk about two theories which describe different aspects of nature, and give the same predictions where they overlap. I would call that one theory.

    Also, my impression is that the concept of constructivism the way you present it in the OP, underestimates the power of scientific experiment and the scientific method as a kind of objective step in between theory and human experience. Several persons can share a scientific model without loss of precision, and separately apply it to experiments. This has worked so well in the past, and I think that the very solipsistic language that often comes with the popular accounts of constructivism, like the first paragraph in your quote, really underestimates the level of objectivity which we have attained using science.

    Cheers

  11. David Marjanović says:

    I would call that one theory.

    I wouldn’t. In the kinds of situations we’re used to, classical physics and relativity make the same predictions (to within too many decimals to measure), yet they’re very different theories.

  12. Jadehawk says:

    I was contemplating whether I should continue this discussion before reading the book… and I’d rather not, overall, but I just wanted to give two quick responses:

    I didn’t know model-dependent realism even had a name. I thought it had been uttermost basic science theory for a long time now. To pull examples from physics, everyone knows quantum theory and relativity contradict each other, and both contradict some observations that the other explains, so both of them have to be wrong somehow,

    I think the point here is not that theories are models (because that would indeed be stating the bleeding obvious), but that facts and observations are, too (I believe Kristoff the Obnoxious was calling that “the theory-laden-ness of observation”)

    Also, my impression is that the concept of constructivism the way you present it in the OP, underestimates the power of scientific experiment and the scientific method as a kind of objective step in between theory and human experience. Several persons can share a scientific model without loss of precision, and separately apply it to experiments

    I don’t actually have any idea what these two sentences mean, sorry :-(

    I don’t know what “objective step between theory and human experience” is supposed to mean, but I’m guessing you’re referring to the filtering function of the scientific method, which filters out certain human biases? If so, no one is actually denying this. Not even constructivism. Similarly, I’m not entirely sure why you think constructivism somehow wouldn’t account for the ability of people to use a scientific model and separately apply it to experiments. Constructivism doesn’t deny the existence of objective reality, it refutes claims that people can objectively perceive and understand it. Two scientists using the same model would of course be able to use it and understand each other and have the same results, since they’re working within the same construction.

    As an example of constructionism, let’s take, for example, this recent post from Deltoid; in it, the AGW denialist claims that CO2 cannot be a pollutant, because it performs useful and needful functions, and nothing about its molecular structure changes(and, for that matter, nothing about what it does in Earth’s atmosphere changes that much, either), so it can’t suddenly become a pollutant. The denialist is of course right that CO2 is always the same molecule with the same chemical properties; the mistake he made was an essentialist one: “pollution” is not a property of a chemical molecule, it’s a social construction: a pollutant is a substance defined as “out of place” and perceived by people as harmful or damaging. Now, these perceptions can be aided by cold hard observations of concentration, or increase, or effect on people, plants, animals, etc., but even then it all only becomes pollution by human construction (heavy metal ores for example aren’t “polluted”, even when their existence has created a certain environment. OTOH, much smaller but newly created concentrations that create new changes are often considered “pollution”; a volcano eruption isn’t “pollution”, but a slag spill is; etc.)

    So my point is: “pollution” is socially constructed, but that doesn’t mean that even people who disagree on this construct wouldn’t be able to measure the concentration of substance X in substance Y; it’s just that it takes human interpretation to be able to say that that concentration is or isn’t “contamination”

  13. Alex says:

    Hi,

    I don’t actually have any idea what these two sentences mean, sorry :-(

    I’m sorry, that is entirely the fault of my obtuse language ;)
    All I wanted to say is that the initial explanation of MDR in your quote, for example

    [Model-dependent realism] is based on the idea that our brains interpret the input from our sensory organs by making a model of the world. When such a model is successful at explaining events, we tend to attribute to it, and to the elements and concepts that constitute it, the quality of reality or absolute truth. There is no picture- or theory-independent concept of reality. Instead we will adopt a view that we will call model-dependent realism: the idea that a physical theory or world picture is a model (generally of a mathematical nature) and a set of rules that connect the elements of the model to observations.

    stresses very much the interpretation our individual brains do using sensory input, and that has reminded me a lot of what many of those philosophical relativists spout all of the time. I just wanted to emphasize that we can communicate theories to each other, and replicate experiments, which lets this model dependent realism become much a more powerful tool for establishing an objective reality which in principle every person can agree to, than the “everything is relative” crowd to which unfortunately many (armchair?)philosophers of the postmodern kind seem to belong, would admit. The most important aspect of that for me personally, which I found was missing in the short quote above. We can have a measuring apparatus that is external to our bodies, and which can be identically replicated and used by others to objectively obtain the same experimental results, and that in my opinion adds something qualitatively new to the idea that our brains are merely interpreting sensory input, because there are very simple objective criteria to decide whether another person has measured the same data in an experiment than me. Also, there are nontrivial checks for self-consistency which everyone an apply with respect to theories and experiments. My friend can do a measurement and a theoretical calculation, and I can do that some other time and somewhere else, and we will arrive at the same result consistent with the theory, or not if it is wrong.

    I apologize for the at times incoherent nature of my thoughts here. I think I basically agree with the notions you presented here, I just think that one could maybe make the wording a little stronger in order to drive home the point that what is described here is a far cry from philosophical relativism.

    Time to go home now ;)

  14. Jadehawk says:

    We can have a measuring apparatus that is external to our bodies, and which can be identically replicated and used by others to objectively obtain the same experimental results, and that in my opinion adds something qualitatively new to the idea that our brains are merely interpreting sensory input, because there are very simple objective criteria to decide whether another person has measured the same data in an experiment than me.

    the machines we build to measure things also come from the human brain.

    To use another example: when we do experiments on the behavior of light, we measure the results with various machinery we designed for the purpose. The result is that everyone will measure the same results, namely that sometimes light behaves like a particle, and sometimes like a wave. But that’s model-based observation already; light behaves like light, and the “sometimes like a particle, sometimes like a wave”, while measurable, repeatable, and communicable between people, is still not “objective reality” it’s model-based reality, i.e. reality as understood by the human brain. And since Hawking was talking about physics, he was saying that this model-based reality is best reflected in mathematical models, not even in words; words are one further level of modeling, where a lot of constructivism comes in (since language is fully socially constructed, obviously)

    I should note that not all post-modernism is relativistic in the extreme that people criticize it here. Most of it doesn’t deny the existence of objective reality, it merely points out that humans aren’t equipped to perceive it as such: we only see part of it, and we understand it only through interpretation; which varies, from person to person as much as from culture to culture (which is the part, I think, where Hawking’s idea differs, since he doesn’t talk about the way different people perceive reality differently, but rather how all humans have certain cognitive functions in common so that even something we all agree on to be true due to dilligent scientific observation and research still isn’t “objectively true”, but merely the best, individual-bias-free, model of it)

  15. David Marjanović says:

    I think the point here is not that theories are models […], but that facts and observations are too

    Sorry, my examples were off, but I still meant the right thing. :-) Admittedly, scientists don’t think about this much in their daily work, but it does come up.

    In the three courses on analytical chemistry that are compulsory for molecular biologists, I was taught how all sorts of detectors work and what sources of systematic and random error they have, as well as more theoretical aspects of measurement. If you build a detector, you make all sorts of assumptions about how physics works; if you’re wrong, the detector is garbage.

    In the biology of macroscopic organisms, you can generally trust your eyes, so one might think such issues don’t come up, a bone is either there or not there; but then you get into individual variation, ontogenetic variation, sexual dimorphism, bad preservation of fossils or dried skeletons or skeletons cleaned by dermestids, and so on, so that the question “does animal X have feature Y” becomes “should animal X be counted as having feature Y”, and there we have a theory-laden fact.

    As an example of constructionism, let’s take, for example […]

    Again I’m surprised that the fact that terminology doesn’t exist in nature but is a set of conventions has a name. But maybe it’s just me — biological nomenclature was ruthlessly essentialist in the times of Linnaeus, and we’re still fighting the vestiges of that thinking, so I’m perhaps unusually aware of it. (…The term constructivism has never been used in that discussion.)

    there are very simple objective criteria to decide whether another person has measured the same data in an experiment than me

    They’re not simple. That’s where we get deep into the kinds of things I alluded to: random error and statistics.

    All you can say in the end is how probable it is that they did not measure the same data and the congruence with your measurements is only due to random chance. That’s the dreaded p value.

  16. Jess says:

    It was funny to come upon your blog Jadehawk by way of making the same discovery as you: encountering, for the first time, Hawking and Mlodinow’s description of model-dependent realism and thinking hmmmm postmodernism in a new jacket.

  17. David Marjanović says:

    (…The term constructivism has never been used in that discussion.)

    …Nor even the term constructionism, for that matter. :-]

  18. K says:

    Great commentary, I got here looking for just such discussion of MDR in reference to postmodern thought.

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