What Darwin did was to show for the first time how we might conceive the natural evolution of species; to suggest that the miracle of the purposive adaptation of organisms to their environment could be explained by purely natural causes without introducing teleological and supernatural agencies to bring the disharmony into harmony. The older mind and logic had seen the action of God everywhere; the new thought and logic were gradually restricting his sphere. Darwin took away a whole province from the teleologist when he merely set up the idea of selection. He towered above himself in that moment. Natural philosophy wrested zoology and botany from the hands of Linné and Cuvier. It destroyed the old idea of a design in the interest of natural law and the general unity of nature. “Allah need create no more.” We cannot emphasise it too much: it was the conceivability that settled the question. Darwin had shown that “it might have been so,” and this possibility stood for the first time in zoology and botany opposed, with all the weight of logic, to the other theory, which was no more understood, but was supplied by imagination to fill a gap—the idea of a special creation of each animal species, the idea that the green tree-frog, had been created amongst the foliage just as he was. The feebler fancy gave way to the better. In this concession lay whole sciences that would have to be entirely transformed on the strength of Darwin’s achievement. Narrow-minded folk have tried to make light of the mere “possibility,” creating a distinction between truth and logical theory. As if all truth were not solely in the human mind! What an age can conceive is true to that age. There is nothing higher in the bounds of time and the development in which we are involved. All truth and science began for humanity in the form of possibilities. Copernicus’s theory was only a possibility when it first came. All that we call human culture has come of the putting together of thousands upon thousands of these possibilities, like so many stones. It is no use raising up against it the figment of “absolute truth.” The main point was that Darwin raised the conceivability of a natural origin of species by the modification of older forms, which were driven ceaselessly to new adaptations under the stress of the struggle for life, to such a pitch that the older possibility of a creation of each species and its deliberate adaptation by supernatural action sank lower and lower. It was a pure conflict of ideas; the greater overcame the smaller—_now_ smaller.