Once more I’ve posted a few comments on BioLogos and got into trouble. Well, that’s been the pattern since 2011, so it’s no surprise. The thread was the old and currently 827-comment-long Buggs/Venema/Swamidass conversation on the population genetics of human origins, a lull in which made me think it was timely to add the kind of cautionary note on the validation of models I’ve sounded here and here.
It was a simple observation, that however consistent a scientific model, established on present populations, is with other models, and however many error bars one calculates, applying it to the distant past adds a further layer of uncertainty. That is because one cannot, in the very nature of things, test the “unknown unknowns” that might apply in that distant situation.
That is why history is always a provisional discipline, the past being interpreted through what are always under-determined data, and subject to reinterpretation even without the discovery of new data. The same is also true of the historical sciences, again in the nature of things. Problems arise when “Science” is given a capital “S” and treated as an ultimate source of knowledge, without due regard being given to its inherent uncertainties, including the human origin of all theories.
A relevant case in point: population genetic phylogenies not infrequently disagree with morphological phylogenies from fossils, as is well-known. One can, and people frequently do, argue for one methodology being correct (and surprisingly, genetics seems to win amongst lay people now, I suspect because it is more technical, whereas morphology appears to be more like artistic connoisseurship even when applied to cladistics). In both cases, though, assuming the data is OK, the problem may lie with with theoretical error – or incomplete information about contingencies.
But both being historical sciences, one can’t go back to check the truth, but only try to refine the models until they agree better. And even if they do finally agree, the evidence of the past is still under-determined. So one ought to retain a very strong sense of “our best provisional estimate”, rather than “the assured results of science.” This is not science-denial, but epistemological caution.
However, the responses to my drawing attention to this were clearly disgruntled, though I did get a “heart” from one moderator. It seemed that for me to suggest that the substantial agreement that had been reached by the population geneticists on the thread is nevertheless open to provisos, from outside the terms of the discussion, was taken to be an assault on the truth of population genetics theory.
Now it wasn’t such a denial at all, though it was a suggestion, on purely logical grounds, that applying population genetics to such a historical situation as human origins might involve unforeseen – and undetectable – errors. This applies to all such models, and the take-home message is simply to observe a bit of humility about the certainty involved in the conclusions. Incidentally, such a need for epistemological humility is equally true of rival interpretations of Genesis – since one cannot visit the past to check, one needs to accept some degree of provisionality in ones understanding, and that undermines neither Scriptural truth nor the value and necessity of drawing and defending conclusions about it.
However, most of the potential errors I had in mind were simpler than this: errors in the assumptions made about past conditions, simplifications thought to be unimportant actually being significant, and so on. That was my point – any historical science ought to recognise that no statistical tools can give one a perfect and objective window into the past.
But as a matter of record, there are – and have been for over a century – doubts amongst evolutionary biologists as to whether speciation arises merely from population genetics continuing over time, or some other factors not yet known. In the case of man, not only do we know of some complex hybridisation events between at least three subspecies or species of Homo, but there is currently, according to a number of palaeoarchaeologists, an entirely unexplained “saltational” gap between that genus and its nearest relatives in the fossils. Something interesting, beyond the pop. gen. model, may well be happening in the exact population under discussion. Caution is advised…
If to mention these elements in the literature (which weren’t, in fact, at the forefront of my mind) “casts doubt on the theory” and is therefore reprehensible, what happened to the principle of seeking to question all ones assumptions? It would appear that instead there’s some kind of psychological need for certainty going on, rather than either a desire simply for the most useful results, or (which should be greater in Evolutionary Creation discourse) the quest for God’s truth. Science is being defended (in a bristly way) as some kind of Absolute, and, rather amusingly, is being “reified” in the particular discipline of population genetics, so that to point out degrees of uncertainty in pop. gen. predictions is tantamount to attacking Truth.
If one can’t see a problem with that, then one has a very different perception of the world from me. If one can’t see a bigger problem with that in the context of a Christian conversation, then it’s even more the case (and I note that nobody, even my “hearted” moderator, was willing to counter my detractors at BioLogos).
For remember, the original question at issue was the existence of Adam and Eve, albeit it in a timeframe I, personally, regard as implausible. These two are first introduced in the book which BioLogos, as well as the “historical Adamists”, acknowledge to be the word of God. As BioLogos states:
We believe the Bible is the inspired and authoritative word of God. By the Holy Spirit it is the “living and active” means through which God speaks to the church today, bearing witness to God’s Son, Jesus, as the divine Logos, or Word of God.
This inspiring God was, it must be agreed on all sides, actually there in the past to witness the population of mankind in all its detail, at every stage. And not only is his Bible authoritative, the statement of faith says, but is acknowledged to speak to the Church, through the Spirit. It is not only data, but a living and active witness to the truth. The disagreement, then, ought to be finally between the fallible human interpretations of this “authoritative word,” some saying it is describing man’s origin simply historically, and others something else. Ultimately, it would appear to be the work of the Holy Spirit to settle the difference, being best placed to do so, through the Scripture itself.
That being so, to use the analogy, as one commenter did, that one would not allow a theologian to contradict a scientist on the position of a comet in the distant past, is saying far more than that science and theology have their own proper spheres – it is to say that the verbal witness of God (even with the best understanding its theological interpreters under the Spirit) must give way to the certainty of science – and not even science, but the particular application of one discipline, population genetics, which (as I have laboured to point out) carries entirely inevitable uncertainties in its application to the question of an original pair.
Now don’t get me wrong – I’m not denying the value of science, and I’m certainly not endorsing a literalist understanding of Genesis. There is epistemological uncertainty in interpreting Scripture, even accounting for the role of the Spirit. But there is nevertheless a clear mismatch between claiming that the Bible is the living and authoritative word of God to the Church, and then in practice taking one branch of historical science as the only certain arbiter on what the Bible actually means.
If it walks like scientism, and quacks like scientism…