Natural Selection and Natural Religion
Natural selection is one of those striking formulas that are so immediately convincing and logical that they scarcely seem to need to be tested in practice and therefore very easily (and perhaps dangerously) come to be taken on trust.
Natural selection theory states that all forms of life produce far more offspring than is required to replace them when they die. The reason why their numbers do not increase dramatically in each generation is that the great majority die before they can reproduce. Those who do survive, become the parents of the generation which follows. These survivors tend statistically to be those best able to cope with the dangers which destroyed their siblings. Since every individual is slightly different and tends to pass its special characteristics on to its offspring, the favourable characteristics that helped the parent to survive to maturity tend also to be found in the offspring, and each generation becomes slightly “fitter” or better able to cope with the needs and perils of life. Thus, it is claimed, over millions of generations, living organisms have tended to become steadily more advanced.
The theory was suggested by Darwin and Wallace to explain the progressive evolution of living things from simple origins. To their fellow scientists, it suggested a mechanism which might explain evolution. But to the 19th century Christian, it had another significance. It provided a terribly convincing alternative to the doctrines of "natural religion".
Natural religion (also called "natural theology") taught that the perfect design of living things is to be attributed to an omnipotent and all-wise creator and is the overwhelming proof of his existence and power. The basic principle was brilliantly presented by Paley:
In crossing a heath, suppose I pitched my foot against a stone , and were asked how the stone came to be there: I might possibly answer, that for any thing I know to the contrary, it had lain there for ever: nor would it perhaps be very easy to show the absurdity of this answer. But suppose I had found a watch upon the ground, and it should be inquired how the watch happened to be in that place; I should hardly think of the answer which I had before given, that for any thing I knew, the watch might have always been there. Yet why should not this answer serve for the watch, as well as for the stone? why is it not as admissable in the second case as in the first? For this reason, and for no other, viz ., that when we come to inspect the watch, we perceive (what we could not discover in the stone) that its several parts are framed and put together for a purpose . . . This mechanism being observed . . . the inference, we think, is inevitable, that the watch must have had a maker; that there must have existed, at some time, and at some place of other, an artificer or artificers, who formed it for the purpose which we find it actually to answer; who comprehended its construction, and designed its use.
(Natural Theology (1802))
The animals and plants of the natural world, Paley taught, equally show evidence of design. They are therefore evidence of the existence of a designer. During the eighteenth and the first half of the nineteenth century, Christianity, or at least Protestant Christianity (and especially British Protestant Christianity) argued itself into a position where religious belief depended heavily upon this interpretation of biology for intellectual support.
Perhaps the first exponent of natural religion in Britain was John Ray . He was also one of the founders of the modern biology; he wrote detailed descriptions of many animals and plants, and in 1691 published a book which was still being reprinted and read in the first half of the nineteenth century - The Wisdom of God manifested in the Works of his Creation. Giving innumerable very specific examples from life, Ray taught that the best possible proof of the existence, wisdom and goodness of God is to be found in the structures and functions of living things. Nothing in animals and plants, he showed us, appears to be useless: everything has been arranged for a good reason. If in a few cases we ourselves cannot see the purpose of some detail, there is likely still to be a purpose known to God, and useful to the creature concerned.
In an age and a country which was fascinated by intricate machinery, and was soon to produce the Industrial Revolution, Ray showed that animals and plants are living mechanisms whose many parts are designed with a far greater subtlety and complexity than could conceivably be achieved by man. Only a supremely wise and omnipotent craftsman - God himself - could have done it. And thus we should deduce that God exists, and is infinitely wise.
Ray's book was one of the earliest of a series of works on the same theme. Addison, who had very great moral and literary influence in the eighteenth and early nineteenth century, took up the argument in the Spectator. The doctrine of natural religion strengthened the faith of a rational and inquiring educated class, which (although it would not allow it to be openly challenged) was probably finding the literal reading of the Old Testament increasingly unconvincing.
But although there was nothing in natural religion to controvert the religion of the Bible, it did little in itself but establish in the mind of the believer the omnipotence and wisdom of God. It added no new moral force of its own, and relied on the Testaments and the established traditions of the Church and of society to fill out the details of devotion and morality. There was always felt to be a danger that belief in natural religion might become separated from Christian doctrine and Christian morality and become no more than an unprincipled and irresponsible deism.
This danger started to appear much greater at the end of the century under the moral stress of the French Revolution, and particularly when Thomas Paine caused a sensation, in 1794, with his brilliantly written and very widely circulated Age of Reason . Paine was a revolutionary: he had played an important propaganda role in the establishment of American independence and he welcomed the French Revolution. He accepted natural religion but did not accept Christianity: in the name of deism, and whilst quoting Addison with approval, Paine ridiculed the Church, reviled the Old Testament, and reduced Jesus to the status of a minor teacher. He regarded the Church as a system of organized self-serving hypocrisy:
All national institutions of churches, whether Jewish, Christian or Turkish, appear to me no other than human inventions, set up to terrify and enslave mankind, and monopolize power and profit.
I do not mean by this declaration to condemn those who believe otherwise; they have the same right to their belief as I have to mine. But it is necessary to the happiness of man, that he be mentally faithful to himself. Infidelity does not consist in believing, or in disbelieving; it consists in professing to believe what he does not believe.
It is impossible to calculate the moral mischief, if I may so express it, that mental lying has produced in society. When a man has so far corrupted and prostituted the chastity of his mind, as to subscribe his professional belief to things he does not believe, he has prepared himself for the commission of every other crime. He takes up the trade of a priest for the sake of gain, and in order to qualify himself for that trade, he begins with a perjury. Can we conceive any thing more destructive to morality than this?
The Church was in urgent need of moral support. Rev. William Paley, probably triggered by Paine, published later in 1794 his Evidences of Christianity . His book was intended to forge an unbreakable bond between natural religion and explicit New Testament Christianity. His book had an immediate impact - the first edition was sold out in a day. It was soon adopted as a university theological textbook. Darwin studied it at Cambridge and was completely convinced. The comments in his Autobiography are significant:
I am convinced I could have written out the whole of the Evidences, with perfect correctness, though not of course in the clear language of Paley. The logic of the book, and I may add of his Natural Theology, gave as much delight as did Euclid. The careful study of these works was the only part of the academical course which, as I then felt, as I still believe was of the least use to me in the education of my mind.
He continues:
I did not at this time trouble myself about Paley's premises; and taking these on trust, I was charmed and convinced by the long line of argumentation.
Paley's argument needs to be read to appreciate its force and conviction. It irresistibly demonstrates (to the reader willing to be carried along) the logical link which Paley believed existed between natural religion and the doctrines of the Church. Having established (he believed) the omnipotence and goodness of God by examples from nature, Paley teaches that because God is good, he will not allow vice to triumph on earth, as it so often does, without a compensating afterlife for humanity. Mankind has to be adequately informed of this arrangement, and of the incentives for correct behaviour on earth: how could this have been achieved, but by the Christian revelation and the Christian miracles? Thus the whole Christian edifice is now to be based on the concept of God as the divine Engineer of the Universe.
Throughout, everything depends on the 'first premise', about which Darwin ‘did not at first trouble himself' - the premise of God, derived from the perfect design of living things. Without that premise - if the perfect design of living things could be otherwise explained - the whole structure of Paley's Christian belief must now fall to the ground. If there was no longer any proof in nature of the omnipotence and goodness of God, there could no longer be any basis for Paleyite Christian belief. Natural religion had been made to support the whole Church, and everything depended upon it. Because of this terrible dependence, the 19th century Christian, confronted with the plausibility of natural selection, found the whole foundation of his faith cut from beneath him.
Natural Selection did not become widely accepted as the governing principle of evolution until it was integrated with Mendelian genetics in the first half of the twentieth century - Darwin presented it as a hypothesis, which could provide a likely but not certain explanation for the evolutionary process of life revealed by the fossil record. But the new hypothesis was convincing enough to introduce an intolerable sense of doubt into mind of the believer in natural religion; and little has been heard of natural religion since.
Yet in a sense there was a natural intellectual link between the new theory and the old. Ray and his contemporaries and successors had believed that animals were intricate mechanisms - machines designed by the Great Engineer of the universe. Eighteenth and early nineteenth century philosophers and theologians were able to believe that animals were no more than machines because Christianity made an explicit distinction between mankind and the other animals. Men and women were not (it was thought) machines, or rather they were more than machines, because the human machine, base as it was, had been specially created by God as a vehicle for consciousness, for the human soul.
Natural Selection made it possible to believe that animals had come into existence by an automatic self-perpetuating process. Animals were still perceived essentially as automata. But whereas previously it was only the functioning of the animal which was thought of as automatic, now the actual design of the "living machine" was believed to be an automatic process. The process by which (it seemed) ape had evolved into man was now believed to be equally automatic.
The intellectual leap from Natural Christianity to the atheism professed by so many scientists in the twentieth century was actually not such a difficult one to make. Having in the 18th century dismissed all other animals as no more than machines, it was not particularly difficult in the later 19th and 20th centuries to put human beings into the same mechanical category and to see a mechanical principle behind the whole developing process of evolution.
But is life a mechanical process? Is there not an important distinction between a machine and a living creature?