How are we to know a teacher, then? The sun requires no torch to make him visible, we need not light a candle in order to see him. When the sun rises, we instinctively become aware of the fact, and when a teacher of men comes to help us, the soul will instinctively know that truth has already begun to shine upon it. Truth stands on its own evidence, it does not require any other testimony to prove it true, it is self effulgent. It penetrates into the innermost corners of our nature, and in its presence the whole universe stands up and says, "This is truth." The teachers whose wisdom and truth shine like the light of the sun are the very greatest the world has known, and they are worshipped as God by the major portion of mankind. But we may get help from comparatively lesser ones also; only we ourselves do not possess intuition enough to judge properly of the man from whom we receive teaching and guidance; so there ought to be certain tests, certain conditions, for the teacher to satisfy, as there are also for the taught.