“Looking at numbers as groups of rocks may seem unusual, but actually it's as old as math itself. The word "calculate" reflects that legacy -- it comes from the Latin word calculus, meaning a pebble used for counting. To enjoy working with numbers you don't have to be Einstein (German for "one stone"), but it might help to have rocks in your head.”

“Yet in another way, calculus is fundamentally naive, almost childish in its optimism. Experience teaches us that change can be sudden, discontinuous, and wrenching. Calculus draws its power by refusing to see that. It insists on a world without accidents, where one thing leads logically to another. Give me the initial conditions and the law of motion, and with calculus I can predict the future -- or better yet, reconstruct the past. I wish I could do that now.”

“River Song: Right then. I have questions, but number one is this - what in the name of sanity have you got on your head? The Doctor: It's a fez. I wear a fez now. Fezzes are cool.”

“The word 'glamour' comes from the word 'grammar', and since the Chomskyan revolution the etymology has been fitting. Who could not be dazzled by the creative power of the mental grammar, by its ability to convey an infinite number of thoughts with a finite set of rules?”

“Don't say you don't have enough time. You have exactly the same number of hours per day that were given to Helen Keller, Pasteur, Michelangelo, Mother Teresa, Leonardo da Vinci, Thomas Jefferson, and Albert Einstein.”

“A novel, in which all is created by the author's whim, must strike a more profound level of truth, or it is worthless.""And yet, I have heard you say that any novel that relieves your ennui for an hour has proved its usefulness.""You have a good memory. It must have been ten thousands of years ago that I uttered those words.""And if it was?""In another ten thousand, perhaps I will agree with them again.""In my opinion, the proper way to judge a novel is this: Does it give one an accurate reflection of the moods and characteristics of a particular group of people in a particular place at a particular time? If so, it has value. Otherwise, it has none.""You do not find this rather narrow?""Madam—""Well?""I was quoting you.”

“This was supposed to be yesterday. I was sitting on the Cardiff/London train, supposedly about to write this very column, and realising something quite terrible. My head was entirely empty. A vast echoing void. Bigger on the inside, but with nothing in it. You could drop a pebble in my brain and wait for an hour to hear it land. No actually, you couldn't - that would be aggressive and unhelpful, so keep your damn pebbles to yourself.”