A few more Kuhnian implications

Thomas Kuhn in The Structure of Scientific Revolutions, addressed in a recent post, condenses many ideas that have already found their way into columns here in the last year or two, so I like him a lot.

One such idea is the way in which perception itself, as opposed to merely the interpretation of perception, is theory-led (or paradigm-led, in his terms). He gives a number of examples in science in which it was simply impossible to see something under one paradigm that became impossible to miss under the new. For example, Aristotelian science saw swinging stones as a question about interrupted falling. Galileo, however, influenced by a century of the new ideas that had replaced the Aristotelian framework, saw them as pendulums, a matter of perpetual oscillation. The different way of seeing led to different questions, different experiments, and the deduction of different principles. Some of the old was lost as the new was gained.

In another example, he points out how John Dalton, distinguishing for the first time mixtures and compounds by his idea that atoms would always combine in whole-number proportions, actually had to discard some important data from Proust, his closest intellectual predecessor, which plainly contradicted the idea. It took many years to reconstitute non-anomalous data – thus showing that the excellent experimentalist Proust made unaccountable mistakes in measurement (or if one were to follow some of the modern quantum theorists, that reality is actually constructed by the experimenter’s presuppositions – I won’t go there!).

As I said above, I’ve commented on such ideas before, eg here, but here’s another semi-personal example, in the context of evolutionary theory, which seems relevant to me. I was a child of the DNA age. I read about the Watson and Crick “secret of life” story as a child in the Reader’s Digest, and learned about it in more detail in A-level zoology in the last years of the 1960s.

One thing that struck me very early on, I recall, was a sense of puzzlement at how the production of particular proteins via the DNA code could account for the physical forms of the creatures I was studying, or for their varied and complex behaviours. I think my teacher shrugged when I asked. The feeling recurred in university biochemistry when, beginning to appreciate the glories of interacting enzyme pathways in the cell, I still had no clear idea how the sum total of that would lead, in one case, to a parasitic snail and, in another, to a bird of paradise. Nobody I asked gave an answer beyond the argument that since DNA and protein synthesis were the blueprint and its execution, clearly form and behaviour must be the result, somehow.

It was a back-of-the-mind question for me in a life more concerned with treating the sick, but I remember being slightly surprised when Dr Arthur Jones (who has commented here in the past) pointed out to me in the late 1980s that biology had no theory of development. It was only about the year 2000, some thirty years after I trained, that “evo-devo” became a tentative speciality in its own right. And the more I read now, the more I realise that form and behaviour are still a complete black-hole within Neodarwinism. One can find a gene whose absence prevents, say, limb development. One can find a protein whose presence will derange normal behaviour. But nobody seriously believes any more that such things indicate that producing a mixture of the right proteins will in itself give you a complete and functioning animal. Or if they do believe it, there are now plenty of voices providing evidence to refute them.

But really, the fact that this was obvious even to me as a kid means it would have been just as obvious to any serious biologist giving the matter a moment’s thought even back in the sixties. Yet very little attempt was made to answer the problems of form and behaviour then, and relatively little progress has been made in it even now. And that’s odd, because the whole purpose of Darwin’s theory of evolution by natural selection was to account for the diversity of form and behaviour.

I suggest that the disparity between the obvious problem and the scientifically perceived problem was caused by a rather more sophisticated version of the observation that to a man with a hammer, everything is a nail. After Watson and Crick and the DNA code, which was a significant paradigm shift within Neodarwinism, everything was seen through the prism of DNA and protein synthesis, because that was the only way of seeing (“nothing in biology makes sense…” etc).

That might be because biologists assumed that, once the business of how one gene->one protein worked was sorted out, the end-points of form and behaviour would just drop into place, even though there was, in retrospect, no obvious reason why they should: in no other branch of experience does a mix of chemicals lead to a particular physical form. But I think it more likely that the whole question just receded into the background of consciousness, because the concept of “form” simply wasn’t inherent to the paradigm.

For a generation or two, until quite recently, one of the central themes of biology, if not the central theme, was not really even a research interest because of the paradigm under which research was done. Even now it’s not quite respectable to talk about “form”, though the problem is as intractable as ever, evo-devo notwithstanding.

So, from Aristotle, through Linnaeus to Darwin, form was the major concern of biology. It has begun to be so again. But during the DNA genocentric half-century, it virtually disappeared from serious view as a problem. I see this as confirmation of Kuhn’s view (like my first biological knowledge also from the early 1960s), that the world we live in, or that we perceive we live in, which amounts to much the same thing, is shaped by the paradigms, scientific or otherwise, that we bring to it.

Maybe there is a lesson there about the “skeptics'” demand that there must be scientific evidence for God if he is to be held to exist. One thing that has been pointed out again and again (though naively denied, in my view, by certain skeptics) is that the materialist paradigm, like all worldviews, is an axiom, not a scientific result. Kuhn states that categorically, incidentally, of all paradigms. It can only therefore be blind to non-materialist entities. Any evidence for God (as for form during the genetic era) will inevitably be be invisible, or discounted as unscientific, or treated as an anomaly to be put on “hold” until some future date.

But that aside, let us suppose that material evidence were forthcoming that supported a scientific belief in God (and perhaps the Intelligent Design project should be in mind here). What that would tell us is that God was visible within the particular scientific paradigm used to obtain and interpret that evidence. And Kuhn says that all humanly-constructed paradigms are subject to periodic revolutions, which can completely change the scope of what is seen to exist in the world. Big issues can come and go.

As argued above, DNA effectively evicted the problem of form from biology for half a century. Similarly Descartes’ corpuscular model outlawed occult forces acting at a distance for a century until Newton levered them back in as “gravity” (leaving them then, and now, as occult as ever). The universe was eternal until the Big Bang gave it a beginning, and there are many voices raised in contemporary cosmology to try to efface that origin again. So it might easily be that the God confirmed by science next year , though not disproved, was simply lost to view in a paradigm shift a few decades later. That, after all is, more or less what happened in early modern science, when thinking God’s thoughts after him seemed, after a while, less obvious than thinking your own.

I suppose the possibility of God’s popping in and out of existence with every changing scientific theory is important particularly if ones belief system incorporates the dictum that science is an ever-converging approach towards the truth of the physical world. Once that convergence were finally complete in a Theory of Everything, one would find out if God were left in the picture or not. But of course, the point of Kuhn’s book is that science isn’t like that at all – its trajectory is as uncertain as all human affairs. He believed we should stop thinking about scientific knowledge as converging on ultimate knowledge, but diverging from what we currently know, since the other is impossible.

So ones knowledge of God’s existence must come from other sources. Perhaps it should be viewed as axiomatic, like the principal of realism for nature.

About Jon Garvey

Training in medicine (which was my career), social psychology and theology. Interests in most things, but especially the science-faith interface. The rest of my time, though, is spent writing, playing and recording music.
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