Again, there are certain species of butterflies which have put on a coloration and a form the effect of which is to aid them in evading the attacks of birds. They were not created so; they have become so; and the precise manner of the becoming will be fully discussed in a later chapter. Let us assume for the moment that this adaptation did not occur by a series of lucky accidents or by any merely mechanical process. Are we, then, bound to attribute it to intelligent contrivance? The question will be best answered by simply putting a case which admits of no doubt. Suppose there were an island in which there were no birds, except such as prey on fishes or on each other, but never on insects. The butterflies on this island, if there were any, would certainly show no trace of protective form or coloration. But at some time or other insect-eating birds might be introduced to the island, as the English sparrow has been introduced in Australia. Then, if the extermination of the butterflies did not proceed too rapidly, we might expect, in the course of generations, to see protective adaptations assumed. But could we expect to see them assumed _in anticipation_ of the advent of the destroyers? We could not. Naturalists, however much they may differ, as they do differ, upon the question as to how protective adaptations actually take place, would all agree that they could not possibly take place in anticipation of needs not yet present. If they did, we should have a miracle, and where miracle comes in knowledge goes out. The cases where conscious, intelligent contrivance would be unmistakably recognizable are just the cases which never occur. The signal service rendered by the champions of the evolution theory, Quos nec fama Deûm, nec fulmina, nec minitanti Murmure compressit Cœlum, is that they conquered the realm of organic nature for true knowledge, and gave the drama of its development a new and profound interest, by showing with an uncompromising courage only equalled by the extraordinarily minute and patient research which justified it, that the _apparent_ instances of divine contrivance with which nature teems must be explained by the responsiveness, the adaptability, of living protoplasm. Needless to say, this demonstration does not in the least _disprove_ the existence of God as a supreme, conscious, personal Intelligence.[13] But it does forbid us to deduce the existence of such a Being from the observation of natural phenomena. A living, developing universe has been set in the place of a Divine Mechanician operating on dead matter. The question, what conception we are to form of the forces of evolution, will be more fully discussed in the succeeding chapters on Biology, as a foundation for views which will afterwards be put forward in relation to Ethics and to Art.