“True opinions are a fine thing and do all sorts of good so long as they stay in their place; but they will not stay long. They run away from a man's mind, so they are not worth much until you tether them by working out the reason. Once they are tied down, they become knowledge, and are stable.”

“There's no chance of their having a conscious glimpse of the truth as long as they refuse to disturb the things they take for granted and remain incapable of explaining them. For if your starting-point is unknown, and your end-point and intermediate stages are woven together out of unknown material, there may be coherence, but knowledge is completely out of the question.”

“Knowledge which is acquired under compulsion has no hold on the mind. Therefore do not use compulsion, but let early education be a sort of amusement; you will then be better able to discover the child's natural bent.”

“Here's something else I'd like your opinion about," I said. "If he went back underground and sat down again in the same spot, wouldn't the sudden transition from the sunlight mean that his eyes would be overwhelmed by darkness?" "Certainly," he replied. "Now, the process of adjustment would be quite long this time, and suppose that before his eyes had settled down and while he wasn't seeing well, he had once again to compete against those same old prisoners at identifying those shadows. Would he make a fool of himself? Wouldn't they say that he'd come back from his upward journey with his eyes ruined, and that it wasn't even worth trying to go up there? And would they -- if they could -- grab hold of anyone who tried to set them free and take them up there and kill him?”

“Man is a prisoner who has no right to open the door of his prison and run away... A man should wait, and not take his own life until God summons him.”

“All is flux, nothing stays still”

“Whereas, our argument shows that the power and capacity of learning exists in the soul already; and that just as the eye was unable to turn from darkness to light without the whole body, so too the instrument of knowledge can only by the movement of the whole soul be turned from the world of becoming into that of being, and learn by degrees to endure the sight of being, and of the brightest and best of being, or in other words, of the good.”