thinking makes it so

There is grandeur in this view of life…

Physics into physics won’t go

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I’ve read Chapter 4 of Stuart A Kauffman’s Reinventing the Sacred several times in the hope that I’ll finally get the point. But I still don’t. The chapter is called The Nonreducibility of Biology to Physics. But each time I read it I end up thinking that if he’s right that biology isn’t reducible to physics then physics isn’t reducible to physics either.

[Follows Not thumping but pumping as sixth in a series on Stuart A Kauffman’s Reinventing the Sacred which began with Reinventing the sand dune.]

Last time I focused on the word ‘function’ as it is used in biology, and tried to dissolve the conundrum Kauffman thinks he sees in it.

I now want to focus on what I see as the other main point he is trying to make in the chapter.

Isaac Newton by William Blake

Isaac Newton by William Blake

Several times he asks and answers the question whether a physicist could deduce the evolution of the biosphere:

One approach would be, following Newton, to write down the equations for the evolution of the biosphere and solve them. This cannot be done.

[Another could be] to simulate the entire evolution of our very specific, historically contingent biosphere.

He gives a number of reasons why attempts like these are doomed to failure.

One is that

The biological world straddles the quantum-classical boundary. For example, about seven photons cause a rod in your retina to respond…

But if the biological world straddles the quantum-classical boundary, surely so does the physical world? I don’t understand quantum mechanics in detail, but one thing I thought I understood was that, in our current state of knowledge, we need quantum mechanics to comprehend what we think is true about the universe. And that includes what we think is true of a universe which is like ours except it has no living things in it.

He gives the example of a stray cosmic ray which causes a mutation in a genotype which then gets selected for and so adds to and changes the biosphere. But couldn’t a stray cosmic ray also have an effect on a local climactic event which then alters the path of a growing storm?

Alan Turing in slate

Alan Turing in slate

Another reason is from mathematics: real numbers, rational numbers and irrational numbers, and what these mean for different orders of infinity:

Alan Turing proved years ago that most real numbers could not be computed—that is, he showed that there was no effective procedure, or algorithm, to compute them. … If most irrational numbers [= a subset of real numbers] are not computable, … [then] there is no algorithm to generate the supposed infinite list of statements in a lower level, or more basic, language that will “reduce” a statement in a higher language to the lower one.

Thus the physicist cannot simulate the evolution of this specific actual biosphere…

…She cannot write down equations and solve for the forward evolution of the biosphere to deduce the occurrence due to natural selection of specific organs such as the heart, and she cannot simulate the evolution of this specific biosphere with its hearts…

But again wouldn’t these also have implications for storms, currents and whirlpools?

He talks of hearts and tigers being ‘real’ in that they have independent causal influence on the world. But again wouldn’t a storm or a whirlpool also count as real for an equivalent reason?

I am not trying to claim there is no difference between a storm and a whirlpool on the one hand and a heart and a tiger on the other. But I haven’t yet seen anything in Kauffman’s chapter 4 to explain why ‘emergence’ – or a particularly significant kind of ‘emergence’ – would apply to hearts and tigers but not to storms and whirlpools.

There is of course a significant difference between hearts and tigers on the one hand and storms and whirlpools on the other. We could say that hearts and tigers are living while storms and whirlpools are not. But that is not particularly helpful – we need to dig deeper.

The significant difference is that hearts and tigers are part of a self-replicating context whereas storms and whirlpools are not. Tigers are self-replicating and hearts are components of self-replicating entities. Storms and whirlpools do not replicate themselves.

I think I’ll stop there, because I want to turn to another book which has been baffling me for overlapping reasons: Jerry Fodor and Massimo Piattelli-Palmarini’s What Darwin Got Wrong.

© Chris Lawrence 2011.

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5 Responses

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  1. Back in graduate school when I was struggling with this question of reductionism, Heisenberg’s uncertainty principle which operates on the quantum level was one of the key factors in convincing me that the assumption of complete determinism made by traditional reductionism could not be justified. There would always be an element of unpredictability which, by definition, scientists could not overcome. And in that sense, reductionism is no more valid for physics than for biology or psychology or weather prediction.

    I agree with you that Kaufman is opaque just when one most needs clarity. Reading him I was never sure whether my difficulty in fully understanding him was do to his inability to write (or possibly think) clearly, my own intellectual limitations, or lack of knowledge about quantum physics.

    But as I said before, I do find what I think is Kaufman’s hidden agenda quite distracting. It seems to me that he already has decided that there is something which he wants to call “God,” and that requires the rejection of absolute reductionism. The problem with this for me is that it does not take on the question of reductionism in its own right. And in terms of science, it is a question that deserves examination wherever the answer may lead us.

    In that context, I am looking forward to reading Aping Mankind: Neuromania, Darwinitis and the Misrepresentation of Humanity by Raymond Tallis. I dare say I am booking in for a fair amount of brain work, but Tallis is a distinguished neurologist and a committed atheist. His view is that consciousness simply cannot be explained on the reductionist level. He argues that biophysical scanning of the brain can teach us a lot but will not unlock the essence of human consciousness and our sense of identity and personhood.

    I am convinced that human consciousness is a natural event – not a result of some nonphysical substance (like a soul) separate from our bodies. But I have suspected for all my professional life that traditional reductionism is not an adequate approach to explaining consciousness either. That does not mean I believe in God.

    I do suspect, though, that the origins of science and its determination to separate itself from religious explanations, has given this question a religious/political dimension that makes the examination of reductionism more contentious than other equally difficult questions which science and philosophers address.

    I look forward to your own courageous battle with whatever it is that Kaufman is saying.

    Terry Herman Sissons

    10 July 2011 at 4:39 pm

    • Thanks Terry.

      I think you’ve hit the nail on the head, ie that Kauffman does not take on the question of reductionism in its own right. He uses a critique of reductionism to justify his alternative of ‘emergence’, and then uses his concept of ‘emergence’ to justify a claim that the sacred is alive and well and immanent in the universe.

      But it won’t wash. If the proposition that there are ‘emergent’ entities is purely entailed by the falsity or incoherence of ‘reductionism’, he can’t then magic ‘sacredness’ out of this ‘emergence’ like a rabbit out of a hat. If meaning and value and the sacred emerged out of matter, then so did pain, terror, cruelty and evil. It’s as if by using the word ‘sacred’ to label what emerges from reality he can shine a light on just the warm and cuddly stuff and ignore everything else which no one in their right mind would call ‘sacred’.

      I see it as ultimately the same kind of intellectual dishonesty as pointing to the beauty of the universe and calling it ‘proof’ of God’s existence.

      Thanks again, Chris.

      Chris Lawrence

      10 July 2011 at 7:51 pm

      • I agree completely, Chris. If you want hold up the universe as proof of God’s existence, you have to take the whole shebang.

        Thank you for saying it so well.

        Terry

        Terry Herman Sissons

        10 July 2011 at 8:42 pm

  2. Sure, physicists can’t calculate the evolutionary process, but the same goes for biologists. They can’t say from what angle a couple of photons would have to hit two organic molecules to make them react and become the DNA’s predecessor, they can only say “Well, there must have been a couple of molecules and photons and something happened and Boom! there’s something similar to DNA.” The same goes for physicists, only they can also provide the underlying models (well, okay actually this one goes out to chemists, but chemistry is nothing but applied physics, too).

    As you already said, physicists do calculate with models based on quantum mechanics, for example in weather forecasting. In quantum mechanics, you can only calculate with probabilities, and to calculate the most probable forecast, we have huge computers and datacenters, to give a pretty solid foundation for the calculations. However, even here we aren’t even close to 100%. When looking at the primordial soup, we have a way less solid base of facts, so the forecasts are not even closely as exact.

    So IMHO saying that biology is more than deeply applied physics, because they can’t calculate what happened, is not also saying like physics is more than physics, but also like saying biology is more than biology, because they can’t either.

    Disclaimer: I’m no scientist or something.

    Jan Winkelmann

    10 July 2011 at 12:42 am

    • Hi Jan,

      Thank you so much for taking the time to respond. I wasn’t trying to make a point about biology vs physics. I was talking specifically about what Stuart Kauffman seemed to be saying in that chapter. Everything he said about biology not reducing to physics seems to apply to different levels in purely physical science too. So if a living thing is an emergent (and therefore irreducibly ‘real’) entity, then so is a storm or a whirlpool – in terms of the arguments he’s using in that chapter.

      I do happen to think there is something ‘special’ about living things. But it’s to do with self-replication and natural selection. That could be a kind of ‘emergence’. But I find Kauffman’s writing incredibly opaque just when it needs to be clear – I’m trying to tease out what he’s actually saying. Considering his subject matter and what he’s claiming it’s not exactly trivial whether his arguments are sound or not.

      Thanks again, Chris.

      Chris Lawrence

      10 July 2011 at 10:40 am


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