Then your words of abuse today may turn into a universally valid principle of denigration, for words are magical formulae. They leave fingermarks behind on the brain, which in the twinkling of an eye becomes the footprints of history. One ought to watch one’s every word. – Franz Kafka, quoted by Gustav Janouch, Conversations with Kafka

How do people go to sleep? I’m afraid I’ve lost the knack. I might try busting myself smartly over the temple with the night-light. I might repeat to myself, slowly and soothingly, a list of quotations beautiful from minds profound; if I can remember any of the damn things. – Dorothy Parker, Here Lies, 1939

It sometimes happens at the end of a dinner, when jokes and walnuts are cracked together, that the paternity of some trite quotation is put in question, and at once the wit of the whole company is set wool-gathering. – Frederic Swartwout Cozzens, “Phrases and Filberts,” Sayings, Wise and Otherwise

Quotation, like much better things, has its abuses. One may quote till one compiles. The ancient lawyers used to quote at the bar till they had stagnated their own cause. – Isaac D’Israeli, “Quotation,” A Second Series of Curiosities of Literature