“and a charge of lying against someone whom you have always found truthful is a very serious thing; a very serious thing indeed.”

“Do not cite the Deep Magic to me, Witch. I was there when it was written.”

“Logic!" said the Professor half to himself. "Why don't they teach logic at these schools? There are only three possibilities. Either your sister is telling lies, or she is mad, or she is telling the truth. You know she doesn't tell lies and it is obvious that she is not mad. For the moment then and unless any further evidence turns up, we must assume that she is telling the truth.”

“Be confident small immortals. You are not the only voice that all things utter, nor is there eternal silence in the places where you cannot come.”

“They did nothing wrong their time here has ended”

“There is a kind of happiness and wonder that makes you serious. It is too good to waste on jokes.”

“God created things which had free will. That means creatures which can go wrong or right. Some people think they can imagine a creature which was free but had no possibility of going wrong, but I can't. If a thing is free to be good it's also free to be bad. And free will is what has made evil possible. Why, then, did God give them free will? Because free will, though it makes evil possible, is also the only thing that makes possible any love or goodness or joy worth having. A world of automata -of creatures that worked like machines- would hardly be worth creating. The happiness which God designs for His higher creatures is the happiness of being freely, voluntarily united to Him and to each other in an ecstasy of love and delight compared with which the most rapturous love between a man and a woman on this earth is mere milk and water. And for that they've got to be free. Of course God knew what would happen if they used their freedom the wrong way: apparently, He thought it worth the risk. (...) If God thinks this state of war in the universe a price worth paying for free will -that is, for making a real world in which creatures can do real good or harm and something of real importance can happen, instead of a toy world which only moves when He pulls the strings- then we may take it it is worth paying.”

“The man who truly and disinterestedly enjoys any one thing in the world, for its own sake, and without caring two-pence what other people say about it, is by that very fact forewarmed against some of our subtlest modes of attack.”

“Did I hate him, then? Indeed, I believe so. A love like that can grow to be nine-tenths hatred and still call itself love.”

“if you do one good deed your reward usually is to be set to do another and harder and better one.”

“You ask whether I have ever been in love: fool as I am, I am not such a fool as that. But if one is only to talk from first-hand experience, conversation would be a very poor business. But though I have no personal experience of the things they call love, I have what is better - the experience of Sappho, of Euripides, of Catallus, of Shakespeare, of Spenser, of Austen, of Bronte, of anyone else I have read.”

“Read and Re-Read--"Re-reading, we always find a new book.” 

“God has not been trying an experiment on my faith or love in order to find out their quality. He knew it already. It was I who didn't. In this trial He makes us occupy the dock, the witness box, and the bench all at once. He always knew that my temple was a house of cards. His only way of making me realize the fact was to knock it down.”

“When two humans have lived together for many years it usually happens that each has tones of voice and expressions of face which are almost unendurably irritating to the other. Work on that. Bring fully into the consciousness of your patient that particular lift of his mother's eyebrows which he learned to dislike in the nursery, and let him think how much he dislikes it. Let him assume that she knows how annoying it is and does it to annoy - if you know your job he will not notice the immense improbability of the assumption. And, of course, never let him suspect that he has tones and looks which similarly annoy her. As he cannot see or hear himself, this easily managed.”

“Love is the great conqueror of lust.”