But at the time of the appearance of the “Origin,” many who sympathised with the general drift of the argument were not yet prepared for the “wider teleology.” Of these Asa Gray may be taken as the representative; and it will be of interest to follow the controversy between him and Darwin as regards design and natural selection. The recently published “Letters of Asa Gray to Charles Darwin” (Macmillan) enable us to follow the correspondence from the side of the great American evolutionist. Writing November 26th, 1860, Darwin refers to one of Asa Gray’s articles on the “Origin”:-- “I grieve to say that I cannot honestly go as far as you do about Design. I am conscious that I am in an utterly hopeless muddle. I cannot think that the world, as we see it, is the result of chance; and yet I cannot look at each separate thing as the result of Design. To take a crucial example, you lead me to infer--that you believe ‘that variation has been led along certain beneficial lines.’ I cannot believe this; and I think you would have to believe, that the tail of the Fantail was led to vary in the number and direction of its feathers in order to gratify the caprice of a few men. Yet if the Fantail had been a wild bird, and had used its abnormal tail for some special end, as to sail before the wind, unlike other birds, everyone would have said, ‘What a beautiful and designed adaptation.’ Again, I say I am, and shall ever remain, in a hopeless muddle.” Elsewhere Darwin suggested that the pouter pigeon, if it occurred wild, and used its inflated crop as a float, would be considered as a striking example of design. This controversy between them continued for many years. We find Asa Gray referring to the argument of the pigeons three years later. Thus he wrote (September 1st, 1863):-- “I will consider about fantastic variation of pigeons. I see afar trouble enough ahead quoad design in nature, but have managed to keep off the chilliness by giving the knotty questions a rather wide berth. If I rather avoid, I cannot ignore the difficulties ahead. But if I adopt your view boldly, can you promise me any less difficulties?” Writing the concluding paragraphs of the “Variations of Animals and Plants under Domestication,” Darwin evidently bore in mind his controversies on the subject with Asa Gray and Lyell, and the attacks of the Duke of Argyll and others. Sending advanced sheets to Asa Gray, he wrote on October 16th, 1867:-- “I finish my book with a semi-theological paragraph, in which I quote and differ from you; what you will think of it, I know not.” In relation to this interesting controversy, I think it well to quote, almost in full, the metaphor by which Darwin enforced his argument that the origin of species by natural selection precluded a belief in design in nature as it was ordinarily conceived at the time.