Now that which I thought it desirable to make perfectly clear, on my own account, and for the sake of those who find their capacity of belief in the Gospel theory of the universe failing them, is the fact, that, in my judgment, the demonology of primitive Christianity is totally devoid of foundation; and that no man, who is guided by the rules of investigation which are found to lead to the discovery of truth in other matters, not merely of science, but in the everyday affairs of life, will arrive at any other conclusion. To those who profess to be otherwise guided, I have nothing to say; but to beg them to go their own way and leave me to mine. I think it may be as well to repeat what I have said, over and over again, elsewhere, that _a priori_ notions, about the possibility, or the impossibility, of the existence of a world of spirits, such as that presupposed by genuine Christianity, have no influence on my mind. The question for me is purely one of evidence: is the evidence adequate to bear out the theory, or is it not? In my judgment it is not only inadequate, but quite absurdly insufficient. And on that ground, I should feel compelled to reject the theory; even if there were no positive grounds for adopting a totally different conception of the Cosmos. For most people, the question of the evidence of the existence of a demonic world, in the long run, resolves itself into that of the trustworthiness of the Gospels; first, as to the objective truth of that which they narrate on this topic; second, as to the accuracy of the interpretation which their authors put upon these objective facts. For example, with respect to the Gadarene miracle, it is one question whether, at a certain time and place, a raving madman became sane, and a herd of swine rushed into the lake of Tiberias; and quite another, whether the cause of these occurrences was the transmigration of certain devils from the man into the pigs. And again, it is one question whether Jesus made a long oration on a certain occasion, mentioned in the first Gospel; altogether another, whether more or fewer of the propositions contained in the "Sermon on the Mount" were uttered on that occasion. One may give an affirmative answer to one of each of these pairs of questions and a negative to the other: one may affirm all, or deny all.