SPINOZA denies the existence of the Devil, and says, in the _Short Treatise_, that if he is the mere opposite of God and has nothing from God, he is simply the Nothing. But if a philosophical doctrine be true, it does not follow that as it stands it is applicable to practical problems. For these a rule may have to be provided, which, although it may not be inconsistent with the scientific theorem, differs from it in form. The Devil is not an invention of priests for priestly purposes, nor is he merely a hypothesis to account for facts, but he has been forced upon us in order that we may be able to deal with them. Unless we act as though there were an enemy to be resisted and chained, if we fritter away differences of kind into differences of degree, we shall make poor work of life. Spinoza himself assumes that other commands than God’s may be given to us, but that we are unhesitatingly to obey His and His only. “Ad fidem ergo catholicam,” he says, “ea solummodo pertinent, quæ erga Deum _obedientia_ absolute ponit.” Consciousness seems to testify to the presence of two mortal foes within us—one Divine and the other diabolic—and perhaps the strongest evidence is not the rebellion of the passions, but the picturing and the mental processes which are almost entirely beyond our control, and often greatly distress us. We look down upon them; they are not ours, and yet they are ours, and we cry out with St. Paul against the law warring with the law of our minds. Bunyan of course knows the practical problem and the rule, and to him the Devil is not merely the tempter to crimes, but the great Adversary. In the _Holy War_ the chosen regiments of Diabolus are the Doubters, and notwithstanding their theologic names, they carried deadlier weapons than the theologic doubters of to-day. The captain over the Grace-doubters was Captain Damnation; he over the Felicity-doubters was Captain Past-hope, and his ancient-bearer was Mr. Despair. The nature of the Doubters is “to put a question upon every one of the truths of Emanuel, and their country is called the Land of Doubting, and that land lieth off and furthest remote to the north between the land of Darkness and that called the Valley of the Shadow of Death.” They are not children of the sun, and although they are not sinners in the common sense of the word, those that were caught in Mansoul were promptly executed.