Clarification of the limits to self organisation
|October 31, 2010||Posted by Richard Johns under Intelligent Design|
In the couple of weeks since I posted a summary of my work on self organisation, I’ve been hoping to receive criticism – none so far unfortunately. However, by trawling the web I did find some anonymous comments. While these were mostly of low quality, some recurrent objections have made me want to clarify a couple of points.
Clarification #1 “Quantheory”, a grad student in physics, criticises the applicability of the results to evolution. He writes:
“… evolution is not described by the search for one specific target. Rather, there is a large range of living things that can exist in many different environments”.
Of course this is true. Nevertheless it doesn’t contradict anything I say in my paper. I’m examining the claim that living organisms (more generally, large and irregular objects) can self organise. The number of possible living organisms simply isn’t relevant to this question, and so isn’t considered in the paper. Recall that a self-organising object is strongly preferred by the dynamics, so that it appears much more quickly and probably than it would in a purely random system.
The author may be suggesting that evolution isn’t a case of self organisation, after all. Perhaps there are so many possible kinds of life that some kinds at least are likely to have emerged even by pure chance, given a few billion years? I hope s/he is not, for this notion is ridiculous, as for example Richard Dawkins has pointed out:
“It is true that there are quite a number of ways of making a living – flying, swimming, swinging through the trees, and so on. But, however many ways there may be of being alive, it is certain that there are vastly more ways of being dead, or rather not alive. You may throw cells together at random, over and over again for a billion years, and not once will you get a conglomeration that flies or swims or burrows or runs, or does anything, even badly, that could remotely be construed as working to keep itself alive.”
(R. Dawkins, The Blind Watchmaker, Penguin Books, 1988, p. 9)
Dawkins, perhaps more than anyone else, has emphasised that evolution (as standardly conceived) is not an unguided random process, since it is directed by natural selection. He considers, for example, the production of part of the protein haemoglobin by a purely random process. The chance he estimates to be around 10-190. (p. 45) Hence Dawkins, very sensibly, stresses that evolution is a non-random process, that generates complex, functional molecules like haemoglobin much more quickly and probably than a random process would. In other words, he says that complex objects like haemoglobin self organise, as defined in my paper.
(On the topic of Dawkins’ The Blind Watchmaker, I must acknowledge the significant role of this book in the development of my ideas. Reading it years ago I was strongly impressed by his statement of the problem of the complexity of life, and its need for a special solution. In his treatment of complex objects he stressed that they have a “heterogeneous structure” (p. 6), which corresponds to my notion of irregularity. But what made the biggest impact was the obvious inadequacy of his (neo-Darwinian) mechanisms for self organisation. It seemed immediately clear that the mechanisms he proposed would do no better than pure chance, and since then I have occasionally tried to find a mathematical basis for this intuition.)
Clarification #2 concerns my statement that self organisation requires no interaction with an external system. Some critics have pointed out that organisms have complex interactions with their environments, and so argued that my results do not apply to evolution.
The need for some such restriction on self organisation should be obvious enough, since we are talking about self organisation, not being organised by something external. When a sculptor carves a piece of rock, for example, the form that emerges after a few weeks cannot be regarded as a product of the rock. Basically anything can happen in a system, if subjected to suitable external forces.
But is evolution self-organisation, or is it a product of external forces? Well it does depend on what you choose to be the “system” under consideration. A common trick in mechanics, in analysing the behaviour of two interacting bodies, is to lump them together, considering them parts of one system. Then you have an isolated system, and can write down a lagrangian.
In a similar way, in order to apply my results to evolution, one needs to find an isolated system within which evolution occurs. The obvious choice would be the whole earth, or perhaps the biosphere, since this contains all interactions between organisms and their environments. The possible snag is that this doesn’t include the sun, and its rather important radiation (and the moon’s too) as well as the solar and lunar gravity, etc. One could instead use the whole solar system, but I don’t think this is necessary for a couple of reasons.
First, while the sun and moon act on the biosphere, the biosphere doesn’t act on them. It’s not an interaction. So the actions of the heavenly bodies can be modelled by forcing functions, rather than by being included in the system.
Second, these external actions are simple, regular, periodic, and so on. Though there are some variations, these are random, or at least not likely to be correlated with the structures of living organisms. Of course the sun in particular is necessary for (most of) life, since it drives photosynthesis. But it is not likely to be a source of the complexity of living organisms.
I think a useful illustration here compares the two external inputs that most computers have: the power cord, and the internet signal. The power cord is of course essential for the computer to operate, as otherwise it would quickly “die”, as (most of) the biosphere would if the sun were turned off. The power cord is just a regular sine wave, however, and so cannot be a source of information. If you want to read War and Peace, for example, and you don’t have the file yet, then you won’t be able to compute it from the power signal. You can get it from the internet, of course, but this is an irregular string of bits.
So my results should, in principle, be applicable to the biosphere. At least, I don’t see why they wouldn’t apply. It may seem extravagant to analyse such a large and complicated system in physical terms, yet it is possible to study the whole biosphere in terms of energy, matter and entropy flows, and I think information is in some ways similar to these. I showed in my paper, for example, that there are conservation laws for things like complexity and information.
Finally, it seems to me that intricate causal interactions sometimes have magical powers ascribed to them. With regard to single systems, we usually have strong GIGO (garbage in, garbage out) intuitions, which I believe are fundamentally correct. But talk of structures emerging from complex interactions seems somehow to slip past these intuitions. To see how interaction, in general, has no special abilities, consider an ignorant person, locked in an empty room, trying to write down a history of Canada. Of course there is little chance of success. Adding a second ignorant person, letting the two interact as you please, makes no difference at all.