Let us grant, however, since the thing is not abstractly inconceivable, that eggs really have no structure. To what, then, shall we attribute the formation of birds? Will it follow that evolution, or differentiation, or the law of the passage from the homogeneous to the heterogeneous, or the dialectic of the concept of pure being, or the impulse towards life, or the vocation of spirit is what actually hatches them? Alas, these words are but pedantic and rhetorical cloaks for our ignorance, and to project them behind the facts and regard them as presiding from thence over the course of nature is a piece of the most deplorable scholasticism. If eggs are really without structure, the true causes of the formation of birds are the last conditions, whatever they may be, that introduce that phenomenon and determine its character—the type of the parents, the act of fertilisation, the temperature, or whatever else observation might find regularly to precede and qualify that new birth in nature. These facts, if they were the ultimate and deepest facts in the case, would be the ultimate and only possible terms in which to explain it. They would constitute the mechanism of reproduction; and if nature were no finer than that in its structure, science could not go deeper than that in its discoveries. And although it is frivolous to suppose that nature ends in this way at the limits of our casual apprehension, and has no hidden roots, yet philosophically that would be as good a stopping place as any other. Ultimately we should have to be satisfied with some factual conjunction and method in events. If atoms and their collisions, by any chance, were the ultimate and inmost facts discoverable, they would supply the explanation of everything, in the only sense in which anything existent can be explained at all. If somebody then came to us enthusiastically and added that the Will of the atoms so to be and move was the true cause, or the Will of God that they should move so, he would not be reputed, I suppose, to have thrown a bright light on the subject.