In the last few posts, I’ve been trying to point out the epistemological limits of science (and how they are routinely transgressed). In particular, I’ve tried to show how “contingency” and “randomness” are, in effect, epistemological black boxes in science. To say something is random, in science, should mean nothing more than “we do not fully understand the causes, and cannot predict the effects.”
Today I want to focus on the randomness of mutations, which as I tangentially mentioned in the last post is properly understood, in evolutionary theory, to mean only “random with respect to fitness”. What that means, of course, is that, if one explores genetic mutations overall, there appears to be no direct correlation with fitness – mutations are not simply the addition of new adaptive features.
In fact, although I’m too lazy to look up the estimates just now, I believe it’s the case that the majority of mutations are highly deleterious and eliminated by “purifying selection” – which in English simply means the organism dies. Nearly all the rest are near-neutral – slightly deleterious or slightly advantageous. Since it is notoriously hard to measure such things, neutral theorists disagree on the proportions. Classically neutral theory worked on the basis that most non-selected alleles that become fixed are slightly deleterious, but some versions of the theory allow for a higher proportion of marginally advantageous ones. Remember, though, that these estimates regarding what is subject to selection are all based on modelling – and we should always remember statistician George Box’s adage that “All models are wrong, but some are useful”.
But all agree that significantly beneficial mutations are extremely rare – to the extent that it’s hard to find anyone willing to put a percentage on it. That’s why Darwinism has always had recourse to the extremes of geological time, and is always embarrassed, or ought to be embarrassed, by instances of rapidly occurring adaptive changes.
From Darwin’s time, when the question was just about variation of traits, to today’s genomic era, such observations have led immediately to the conclusion that variation or mutation occur “randomly”, meaning undirectedly, with natural selection bringing order to the process. But this conclusion is actually metaphysical or theological, not scientific, as I have been attempting to point out in these articles.
Actually, since scientifically speaking “random” can never mean more than “unpredictable because causes unknown”, “random with respect to fitness” means only “unpredictable with respect to fitness.” Theologically, other explanations are infinitely preferable to “ontologically random” or “undirected”, and I’ll explore just one.
The problem comes from science’s self-restriction to efficient causes: the issue is seen purely in terms of “mutations are the source of variation: do they all invariably produce useful variation?” To which the answer is, of course, “No.” But suppose one allows final causation into the picture, as one must in theistic evolution? The issue then becomes, “mutations occur for various reasons and purposes, including beneficial variation: which of them are intended for evolutionarily creative purposes?”
I was alerted to this line of thought by good old Asa Gray, Darwin’s correspondent and possibly the first theistic evolutionist, who in discussing variation wrote:
The origination of the improvements, and the successive adaptations to meet new conditions or subserve other ends, are what answer to the supernatural, and therefore remain inexplicable. As to bringing them into use, though wisdom foresees the result, the circumstances and the natural competition will take care of that, in the long-run. The old ones will go out of use fast enough, except where an old and simple machine remains still best adapted to a particular purpose or condition — as, for instance the old Newcomen engine for pumping out coal-pits.
In other words, he saw the variations which produce the innovations seen throughout biology as God’s creative (and contingent) acts – even as supernatural acts – and natural selection as merely a “market force” ensuring that the new, improved, models are what survives.
Here’s an analogy. Back in World War II my father spent a period at the RAF’s underground nerve centre at Uxbridge, receiving secret coded messages. He wasn’t an Alan Turing, sadly – he never understood any of them, being paid only to translate the morse code accurately and take the messages to others to de-encrypt. But you’ll be aware that at various stages in the war, armies of intelligence people were listening in to, and decoding, all Germany’s encoded radio traffic, with specific aims in view: for example, to look out for the vital messages that would portend the threatened invasion.
The vast majority of messages were utterly trivial. Requests for routine supplies, minor redeployments, and so on. The significant stuff, as far as the codebreakers were concerned, might constitute one in a million, or less, of the things they laboriously decoded, and discarded.
From a scientific point of view, it would be accurate to say that the whole body of messages was “random with respect to invasion.” But it would be quite wrong to say that invasion instructions were therefore fortuitous and undirected.
Here’s a second analogy (also in the warfare field, I’m afraid – I’m still affected by my former comparison of natural selection to history and by the old concept of evolution as a struggle for survival). Imagine current intelligence personnel controversially trawling through the bank records of hundreds of people they consider capable of Islamist radicalisation. Telephone bills, supermarket bills, and other “neutral” expenditure attract no interest. Even the large purchase of a secondhand car means nothing significant. Here’s a family that blows a lot of money on a known fraudulent organiser of pilgrimages to Mecca, which is very sad for them but of no interest to Homeland Security.
But what’s this? A couple with Saudi origins has just purchased two one-way tickets to Turkey. That single purchase is the one that indicates a potential security risk: the family has “evolved” (if you like) from mundane innocence to potential terrorism.
Applying these analogies, suppose that mutations occur not blindly, but for various reasons, ultimately within God’s teleological purposes (ignoring any supposed internal teleology – I’m accepting conventional Neodarwinism for this discussion). Not all of these purposes are creative – some are more or less lawlike, which is why studies attempting to apply mutation commercially to plants foundered on the fact that the same old useless mutations turned up over and over again. Many may be “pathological”, just as every living thing is subject to failures and traumas under God’s providence.
Yet suppose that, on the rare occasions when God creatively decides to modify life, he introduces some variation which is entirely positively determined with respect to fitness, and which he providentially preserves sufficiently for it to be guaranteed to become fixed according to the statistical lawlikeness of population genetics.
Scientifically such a variation would be contingent, unpredictable and, therefore, “random” according to the limited definition of randomness permissible in science. But “random with respect to fitness” it most certainly would not be – that description would apply only to mutations considered en masse, which is all that our limited science of efficient causes can see.
Such considerations matter because of the persistent error of many Evolutionary Creation proponents in confusing epistemological randomness with the metaphysical assumption of ontological randomness assumed by so many biologists. They then seek to justify God’s creation of such randomness in terms of nature’s “freedom”, and therefore to treat randomness as a reason to deny, or at least doubt, that evolution meets God’s specific ends.
The fact that Job plainly proclaims the creative pride of God in the detailed nature of ostriches, or leviathan, or behemoth, or warhorses; the fact that Jesus attributes the form of the lilies of the field to God’s wisdom and beneficience, and so on is therefore ignored, and replaced (simply because scientific randomness is illegitimately interpreted as ontological randomness) by an agnostic unwillingness to affirm God as the sole Creator of “the world and everything in it.”
Such ideas don’t come from the Bible, nor from Christian tradition, and I have shown sufficiently, I think, that they cannot be legitimately reached from science. So where do such ideas come from – and why should anybody be expected to take them seriously?