The equation above is the mathematical metaphor I use to understand & discuss conventional evolution. The value of Y represents the population of a particular organic configuration at a point in configuration space. Configuration space is a multidimensional space of many dimensions. The left-hand side of the equation represents the rate of change of Y at the relevant point. The first term on the right-hand side is a multidimensional diffusion term: For this reason, I use the House Operator (which is simply a multidimensional version of the three-dimensional Del operator). The second term on the right-hand side represents either a multiplying or decaying population at a point in configuration space: The decay or growth function V will vary over the multidimensional space, and perhaps even with time. Strictly speaking the diffusion constant A could also be a function of time and space. I discuss this equation further here:
Quantum Non-Linearity: The Mathematics of the Spongeam. (quantumnonlinearity.blogspot.com)
Quantum Non-Linearity: On Structuralism and the Spongeam (quantumnonlinearity.blogspot.com)
Quantum Non-Linearity: Evolution: Naked Chance? (quantumnonlinearity.blogspot.com)
The equation has the potential to hide many informational complexities in the factors A and V. My use of this equation is not to imply that I've committed myself to conventional evolution, but I'll be using it to discuss a post by biochemist and evangelical atheist Larry Moran. This post can be found here: Sandwalk: Evolution by chance.
Moran starts by quoting evolutionist Jerry Coyne:
JERRY COYNE: This brings up the most widespread misunderstanding about Darwinism: the
idea that, in evolution, "everything happens by chance" (also stated
as "everything happens by accident"). This common claim is flatly
wrong. No evolutionist—and certainly not Darwin—ever argued that natural
selection is based on chance ....
True, the raw materials for evolution—the variations between
individuals—are indeed produced by chance mutations. These mutations occur
willy-nilly, regardless of whether they are good or bad for the individual. But
it is the filtering of that variation by natural selection that produces
natural selection, and natural selection is manifestly not random. (p. 119)
MY COMMENT: No problems in the foregoing as far as I'm concerned. Let me echo this: Natural selection is not random: It effectively provides an envelope of constraint on the random walk of evolutionary diffusion. This constraint is represented by the population term VY in my equation above; in some parts of configuration space organisms die out and in other parts the population increases. The factor V describes mathematically a set of interconnected channels in configuration space along which the random diffusion is channeled - this is what I refer to as the spongeam. This factor acts as a constraint which by definition means that the evolutionary dynamic isn't random: it is a highly constrained process which results in some walks dying out and some being allowed through. But as we will go onto to see other forms of evolution that Larry Moran pins his hopes on are also not freely-random in the sense that they act without constraint.
LARRY MORAN COMMENTS: It's extremely important to notice that Coyne is referring to NATURAL SELECTION (or Dawinism) in this passage. Natural selection is not random or accidental, according to Coyne. This passage is followed just a few pages later by a section titled "Evolution Without Selection."
JERRY COYNE: Let's take a brief digression here, because it's important to appreciate
that natural selection isn't the only process of evolutionary change. Most
biologists define evolution as a change in the proportion of alleles (different
forms of a gene) in the population.
[Coyne then describes an example of random genetic drift and continues
...] Both drift and selection produce the genetic change that we recognize as
evolution. But there's an important difference. Drift is a random process,
while selection is the antithesis of randomness. Genetic drift can change the
frequencies of alleles regardless of how useful they are to their carrier.
Selection, on the other hand, always gets rid of harmful alleles and raises the
frequencies of beneficial ones. (pp. 122-123)
Larry then quotes Richard Dawkins' response to Jerry (my emphases):
RICHARD DAWKINS: Coyne is right to identify the most widespread misunderstanding about
Darwinism as 'the idea that, in evolution, 'everything happens by chance' ...
This common claim is flatly wrong.' Not only is it flatly wrong, it is
obviously wrong, transparently wrong, even to the meanest intelligence (a
phrase that has me actively restraining myself). If evolution worked by chance,
it obviously couldn't work at all. (p. 427)
I think Richard is essentially right but Larry's intuitive instincts rebel:
LARRY MORAN COMMENTS: That last sentence is jarring to many scientists, including me. I think
that the Dawkins' statement is 'obviously wrong' and 'transparently wrong'
because, as Coyne pointed out, evolution by random genetic drift can occur by
chance. [Let's not quibble about the meanings of 'random' and 'chance."
That's a red herring in this context.] Clearly, evolution can work by chance so
why does Dawkins say it can't?
It's not because Dawkins is unaware of random genetic drift and Neutral
Theory. The explanation (I think) is that Dawkins restricts his definition of
evolution to evolution by natural selection. From his perspective, the fixation
of alleles by random genetic drift doesn't count as real evolution because it
doesn't produce adaptations. That's the view that he described in The Extended
Phenotype back in 1982 and the view that he has implicitly supported over the
past few decades [Richard Dawkins' View of Random Genetic Drift].
This is one of the reasons why we refer to Dawkins as an adaptationist
and it's one of the reasons why so many of today's evolutionary
biologists—especially those who study evolution at the molecular level—reject
the Dawkins' view of evolution in favor of a more pluralistic approach.
MY COMMENT: Coyne and Dawkins are absolutely right: This sentence by Dawkins says it all: If evolution worked by chance, it obviously couldn't work at all. (p. 427). Moreover, the antithesis of this, namely that evolution is pure, undressed chance, is clearly false: Not only is it flatly wrong, it is obviously wrong, transparently wrong, even to the meanest intelligence.
It is possible to incorporate the genetic drift scenario into my mathematical metaphor: In genetic drift the value of V is zero. In the part of configuration space where V = 0 random walk gets a free hand as parts of the organic configuration (i.e. the DNA) drift at random, where in this region of configuration space the incremental changes of the walk do not immediately impact the growth or decay of the population value Y. But this unconstrained random walk cannot persist indefinitely: As is obvious and transparent to most people (like Coyne and Dawkins) the statistical weight of disorder is so great that unconstrained random walk, given enough time, will break down the highly organised complexity needed for self-maintaining, self-perpetuating structures to be viable. In order to prevent this a value of V other than zero must kick in at some point to maintain organization. Chance certainly operates in evolution, but it is never naked chance, it is always dressed chance; that is, random walk constrained by V; even neutral drift is ultimately constrained by V. So, whether or not Coyne and Dawkins accept that evolution can happen when V is neutral, they remain right about evolution never being a fully random walk process. Anyone without prior prejudice can see that.
TAKE HOME LESSONS
Larry Moran is an evangelical atheist, and this is the motivation for his preference for over-playing the role of randomness. Random distributions, by definition, do not favour particular configurations. As I've said in this blog before randomness spreads the butter of probability as evenly over the contingencies as the constraints on a system allow. As such random distributions appear to lack any sign of a targeted design intention; design intentionality, by definition, has goals and targets and therefore has preferences for certain kinds of contingency. So given that it is impossible to eliminate the contingency implicit in the question "why is there something rather than nothing?", the next best thing for an atheist to do is to deny there is any selective contingency, (selective contingency is a feature we tend to associate with sentient intentionality) and instead opt for the "all contingences are present" view - a preference that has its ultimate expression in multiverse theories.
But in the end Larry's mission fails: Evolution, as is conventionally understood, whilst not necessarily a strictly adaptationist process, nevertheless is far from being naked chance: Rather, it is dressed chance in that for evolution to work random walk must take place within an envelope of constraints encapsulated in the term V, and which ensures that the configurational organization required for self-maintenance & self-perpetuation is maintained. It is an irony that both fundamentalist Christians and some atheists should join with one voice in up-playing evolution's random element: In fact they do so for the same motive - that is, a desire to bill evolution as a random and Godless "natural process". If (repeat if) evolution as conventionally understood explains natural history it would, of course, trace its effectiveness back to God's creative organizing power implicit in V and therefore it does no justice to describe evolution as a "natural process". Genesis 1 with its talk of "separations" is an account of God's organizing power.
Given that the evolutionary process as conventionally understood is a parallel computation and that the lifetime of the cosmos is relatively short, then for evolution to work it demands the input of a high level of starting information. This initial information (embodied in V) gives evolution its requisite high conditional probability. See here:
As a rule fundamentalist Christians are completely unaware of this information argument and persist in up-playing the "naked randomness" line.
***
Larry Moran has also backed another horse which he thinks supports his philosophy; that is, he is utterly committed to the existence of junk DNA. In this respect he has set himself against the de-facto Intelligent Design movement which is utterly committed to the opposite proposition; namely, that intelligently designed life wouldn't contain junk DNA. Both commitments are utterly misplaced.
If life has been intelligently designed by direct intervention, who knows, that intelligence may wish to keep redundant DNA in the genome for inscrutable reasons, just as programmer might want to keep past edits in his code. Or, on the other hand, perhaps that Designer has a very tidy mind and likes to clean up His code. Who knows! Alternatively, the random twists and turns of diffusional evolution may leave junk DNA in the genome. But then some evolutionists may claim that the survivalist rigours of evolutionary pressures would select out this unnecessary & wasteful molecular overhead. So, the conclusion is that the absence or presence of junk DNA could occur for both direct intelligent intervention and via evolutionary processes. Therefore the absence or presence of junk DNA is not strong evidence for either Larry Moran's brand of atheism or the de facto IDist's brand of Intelligent Design.
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