THE unity of the primitive nebulosity must have been, as we have seen, a unity of elements in relation to one another. It is not undifferentiated stuff, but definite molecules existing in definite relations. It is not chaotic, but orderly, and existing in relations which can be thought. Thus the unity of the primitive nebulosity is already rational and intelligible. If this is possible at the outset, then the process of evolution will also be rational and intelligible, and the outcome will also be rational. It is not for us to contend against the existence of a primitive nebulosity either of the solar system or of the sidereal. Nor have we any interest in contending against the discovery of method, order, law in nature. We are glad to sit at the feet of those who can show us the widening bounds of order and law, who can teach us to know the dominion of order and law where we were once unable to discover it. We gladly follow Mr. Herbert Spencer as he leads us on from stage to stage of existence and of knowledge, and shows us how every stage is under law, and that even the very discovery of law is itself subject to law. We may not agree with him either in the general or in the particular, but we are grateful for the wide outlook he has cast over the universe, and for a possible interpretation of the order of nature.