Take away from the domain of knowledge the idea of a creating and presiding intelligence, and there remains no motive for science itself. Professor Tyndall is sagacious enough to see and candid enough to admit that "without moral force to whip it into action the achievements of the intellect would be poor indeed," and that "science itself not unfrequently derives motive power from ultra-scientific sources." Faith in God, as an intelligent creator and ruler of the world, has awakened enthusiasm for scientific investigation among both the Aryan and the Semitic races. The purest and highest form of monotheism is that of Christianity; and in Christendom has science made its largest progress. Not by martyrs for science, but by martyrs for religion, has the human mind been emancipated. Mr. Tyndall says of scientific freedom, "We fought and won our battle even in the middle ages." But the heroes of intellectual liberty have been the heroes of faith. Hundreds of thousands have died for a religious creed; but how many have died for a scientific theory? Luther went to Worms, and maintained his opinions there in defiance of the anathemas of the church and the ban of the empire, but Galileo denied his most cherished convictions on his knees. Galileo was as noble a character as Luther; but science does not create the texture of soul which makes so many martyrs in all the religious sects of Christendom. Let the doctrine of cosmical force supplant our faith in the Almighty, and in a few hundred years science would probably fade out of the world from pure inanition. The world would probably not care enough for _anything_ to care for science. The light of eternity must fall on this our human and earthly life, to arouse the soul to a living and permanent interest even in things seen and temporal. Professor Tyndall says: "Whether the views of Lucretius, Darwin, and Spencer are right or wrong, we claim the freedom to discuss them. The ground which they cover is scientific ground."