With this definition of Eugenics and preliminary statement of its aims before us we may proceed to a somewhat fuller statement of the facts within this field. First let us consider the relation of the science of Eugenics to its parent sciences, biology and sociology, then after mentioning some of the steps in the development of the present eugenic movement, we may describe some of the conditions which give us human beings pause and lead us to appreciate the necessity for a reconsideration of much that enters into our present social organization and conduct. Shortly before the publication of "The Origin of Species," Darwin was asked by Alfred Russell Wallace whether he proposed to include any reference to the evolution of man. Darwin's reply was: "You ask whether I shall discuss man. I think I shall avoid the whole subject, as so surrounded with prejudices; though I fully admit that it is the highest and most interesting problem for the naturalist." This prejudice which Darwin knew would preclude a just consideration of the subject of man's origin and evolution, grew out of the former and long current conception of the position occupied by man in the whole scheme of Nature--of "Man's Place in Nature." This conception, happily obsolete now among thinkers, though occasionally seen lurking in out of the way corners shaded from the light of modern philosophy and science, placed Man and the rest of the universe in separate categories. Man was one, all the rest another. It was for Man's benefit or pleasure that the rains descended, that the corn grew and ripened, that the sun shone, the birds sang, the landscape was spread before the view. For Man's warning or punishment the lightning struck, comets appeared, disease ravaged, insects tormented and destroyed. It was certainly very natural that Man should regard himself as a thing apart, particularly since he was able to control and to regulate Nature, and to take tribute from her so extensively. But the scientist regarded man differently; from him the world learned to recognize man as an integral factor in Nature--as one with Nature, possessing the same structures, performing the same activities, as other animals; subject to much the same control and with much the same purposes in life and in Nature as other living things. There is to-day no necessity to enlarge upon this view. As Ray Lankester puts it: "Man is held to be a part of Nature; a being, resulting from and driven by the one great nexus of mechanism which we call Nature."