Socrates, seeing how unsatisfactory were all physical inquiries, and what evils materialism introduced into society, making the body everything and the soul nothing, turned his attention to the world within, and "for physics substituted morals." He knew the uncertainty of physical speculation, but believed in the certainty of moral truths. He knew that there was a reality in justice, in friendship, in courage. Like Job, he reposed on consciousness. He turned his attention to what afterwards gave immortality to Descartes. To the scepticism of the Sophists he opposed self-evident truths. He proclaimed the sovereignty of virtue, the universality of moral obligation. "Moral certitude was the platform from which he would survey the universe." It was the ladder by which he would ascend to the loftiest regions of knowledge and of happiness. "Though he was negative in his means, he was positive in his ends." He was the first who had glimpses of the true mission of philosophy,--even to sit in judgment on all knowledge, whether it pertains to art, or politics, or science; eliminating the false and retaining the true. It was his mission to separate truth from error. He taught the world how to weigh evidence. He would discard any doctrine which, logically carried out, led to absurdity. Instead of turning his attention to outward phenomena, he dwelt on the truths which either God or consciousness reveals. Instead of the creation, he dwelt on the Creator. It was not the body he cared for so much as the soul. Not wealth, not power, not the appetites were the true source of pleasure, but the peace and harmony of the soul. The inquiry should be, not what we shall eat, but how shall we resist temptation; how shall we keep the soul pure; how shall we arrive at virtue; how shall we best serve our country; how shall we best educate our children; how shall we expel worldliness and deceit and lies; how shall we walk with God?--for there is a God, and there is immortality and eternal justice: these are the great certitudes of human life, and it is only by these that the soul will expand and be happy forever.