For the unity which is implied in the mechanism of the heavens is indeed a unity which is all-embracing and complete. The structure of our own bodies, with all that depends upon it, is a structure governed by, and therefore adapted to, the same force of gravitation which has determined the form and the movements of myriads of worlds. Every part of the human organism is fitted to conditions which would all be destroyed in a moment if the forces of gravitation were to change or fail."[24] But it is unnecessary to multiply illustrations. Having defined the principle we may proceed at once to apply it. And the argument may be summed up in a sentence. As the Natural Laws are continuous through the universe of matter and of space, so will they be continuous through the universe of spirit. If this be denied, what then? Those who deny it must furnish the disproof. The argument is founded on a principle which is now acknowledged to be universal; and the _onus_ of disproof must lie with those who may be bold enough to take up the position that a region exists where at last the Principle of Continuity fails. To do this one would first have to overturn Nature, then science, and last, the human mind. It may seem an obvious objection that many of the Natural Laws have no connection whatever with the Spiritual World, and as a matter of fact are not continued through it. Gravitation for instance--what direct application has that in the Spiritual World? The reply is threefold. First, there is no proof that it does not hold there. If the spirit be in any sense material it certainly must hold. In the second place, gravitation may hold for the Spiritual Sphere although it cannot be directly proved. The spirit may be armed with powers which enable it to rise superior to gravity. During the action of these powers gravity need be no more suspended than in the case of a plant which rises in the air during the process of growth. It does this in virtue of a higher Law and in apparent defiance of the lower. Thirdly, if the spiritual be not material it still cannot be said that gravitation ceases at that point to be continuous. It is not gravitation that ceases--it is matter. This point, however, will require development for another reason. In the case of the plant just referred to, there is a principle of growth or vitality at work superseding the attraction of gravity. Why is there no trace of that Law in the Inorganic world? Is not this another instance of the discontinuousness of Law? If the Law of vitality has so little connection with the Inorganic kingdom--less even than gravitation with the Spiritual, what becomes of Continuity? Is it not evident that each kingdom of Nature has its own set of Laws which continue possibly untouched for the specific kingdom but never extend beyond it?