There used to be a children's book which bore the fascinating title of "The Chance World." It described a world in which everything happened by chance. The sun might rise or it might not; or it might appear at any hour, or the moon might come up instead. When children were born they might have one head or a dozen heads, and those heads might not be on their shoulders--there might be no shoulders--but arranged about the limbs. If one jumped up in the air it was impossible to predict whether he would ever come down again. That he came down yesterday was no guarantee that he would do it next time. For every day antecedent and consequent varied, and gravitation and everything else changed from hour to hour. To-day a child's body might be so light that it was impossible for it to descend from its chair to the floor; but to-morrow, in attempting the experiment again, the impetus might drive it through a three-story house and dash it to pieces somewhere near the center of the earth. In this chance world cause and effect were abolished. Law was annihilated. And the result to the inhabitants of such a world could only be that reason would be impossible. It would be a lunatic world with a population of lunatics.
Now this is no more than a real picture of what the world would be without Law, or the universe without Continuity. And hence we come in sight of the necessity of some principle of Law according to which Laws shall be, and be "continuous" throughout the system. Man as a rational and moral being demands a pledge that if he depends on Nature for any given result on the ground that Nature has previously led him to expect such a result, his intellect shall not be insulted, nor his confidence in her abused. If he is to trust Nature, in short, it must be guaranteed to him that in doing so he will "never be put to confusion." The authors of the _Unseen Universe_ conclude their examination of this principle by saying that "assuming the existence of a supreme Governor of the universe, the Principle of Continuity may be said to be the definite expression in words of our trust that He will not put us to permanent intellectual confusion, and we can easily conceive similar expressions of trust with reference to the other faculties of man."[22] Or, as it has been well put elsewhere, Continuity is the expression of "the Divine Veracity in Nature."[23] The most striking examples of the continuousness of Law are perhaps those furnished by Astronomy, especially in connection with the more recent applications of spectrum analysis. But even in the case of the simpler Laws the demonstration is complete. There is no reason apart from Continuity to expect that gravitation for instance should prevail outside our world. But wherever matter has been detected throughout the entire universe, whether in the form of star or planet, comet or meteorite, it is found to obey that Law. "If there were no other indication of unity than this, it would be almost enough. 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.