I do not know what it was that the man had learned that he desired to forget. My story is not the kind of a story that tells those things. I know, only, that for him to forget was imperative. I know, only, that had he held fast to Ignorance in some things of which he had gained knowledge, it would have been better. For him in some things Ignorance would have been the truest wisdom. Ignorance would have helped him to work out his dreams when Knowledge only hindered by forcing him to spend much time striving to forget. Those who know too much of evil find it extremely difficult to gain knowledge of the good. Those who know too much of the false find it very hard to recognize the true. A too great knowledge of things that are wrong makes it almost impossible for one to believe in that which is right. Ignorance, rightly understood, is, indeed, one of the Thirteen Truly Great Things of Life. And then this man, in learning the value of Ignorance, came perilously near believing that no man could _know_ anything. He came dangerously near the belief that Knowledge is all a mirage toward which men journey hopelessly; a phantom to be grasped by no hand; a will-o'-the-wisp to be followed here and there but leading nowhere. He, for a little, said that Ignorance is the truest wisdom. He believed, for a time, that to say always: "I do not know," is the height of all intelligence. One by one, he saw his intellectual idols fall in the dust of the commonplace. Little by little, he discovered that the intellectual masters he had served were themselves only servants. His intellectual Gods, he found to be men like himself. And so, for a while, he said: "We can know nothing. We can only think that we know. We can only pretend to know. There _is_ no real Knowledge but only Ignorance. Ignorance should be exalted. In Ignorance lies peace, contentment, happiness, and safety." Even of his work--of his dreams he said this. He said: "It is no use." To the very edge of this pit he came but he did not fall in. To accept the fact of the unknowable without losing his faith in the knowable: to recognize the unknown without losing in the least his grip upon the known: to find the Knowledge of Yesterday becoming the Ignorance of to-day and still hold fast to the Knowledge of the present; to watch his intellectual leaders dropping to the rear and to follow as bravely those who were still in the front: to see his intellectual heroes fall and his intellectual idols crumbling in the dust and still to keep burning the fire of his enthusiasm: to find Knowledge so often a curse and Ignorance a blessing and still to desire Knowledge: all this, the man learned that he must do if he would work out his dreams. That which saved the man from the pit of hopeless disbelief in everything and helped him to a clear understanding of Ignorance, was this: he went back again into his Yesterdays.