But there is this great difference between the two cases. Whereas by subsequent inquiry he could ascertain as a matter of fact that the watch was due to intelligent contrivance, he could make no such discovery with reference to the marine bay: in the one case intelligent contrivance as a cause is independently demonstrable, while in the other case it can only be inferred. What, then, is the value of the inference?
If, after the studies of our imaginary teleologist had been completed, he were introduced to the library of the Royal Society, and if he were then to spend a year or two in making himself acquainted with the leading results of modern science, I fancy that he would end by being both a wiser and a sadder man. At least I am certain that in learning more he would feel that he is understanding less—that the archaic simplicity of his earlier explanations must give place to a matured perplexity upon the whole subject. To begin with, he would now find that every one of the adjustments of means to ends which excited his admiration on the sea-coast were due to physical causes which are perfectly well understood. The cliffs stood at the opening of the bay because the sea in past ages had encroached upon the coast-line until it met with these cliffs, which then opposed its further progress; the bay was a depression in the land which happened to be there when the sea arrived, and into which the sea consequently flowed; the successive occurrence of rocks, shingle, and sand was due to the actions of the waves themselves; the segregation of sea-weeds, shells, pebbles, and different kinds of sand, was due to their different degrees of specific gravity; the fresh-water streams ran in channels because they had themselves been the means of excavating them; and the multitudinous forms of life were all adapted to their several habitats simply because the unsuited forms were not able to live in them. In all these cases, therefore, our teleologist in the light of fuller knowledge would be compelled to conclude at least this much—that the adaptations which he had so greatly admired when he supposed that they were all due to contrivance in anticipation of the existing phenomena, cease to furnish the same evidence of intelligent design when it is found that no one of them was prepared beforehand by any independent or external cause.
He would therefore be led to conclude that if the teleological interpretation of the facts were to be saved at all, it could only be so by taking a much wider view of the subject than was afforded by the particular cases of apparent design which at first appeared so cogent. That is to say, he would feel that he must abandon the supposition of any special design in the construction of that particular bay, and fall back upon the theory of a much more general design in the construction of one great scheme of Nature as a whole. In short he would require to dislodge his argument from the special adjustments which in the first instance appeared to him so suggestive, to those general laws of Nature which by their united operation give rise to a cosmos as distinguished from a chaos.