“What went on in No.1’s brain? He painted to himself a cross-section through that brain, painted neatly with grey water-colour on a sheet of paper stretched on a drawing-board with drawing-pins. The whorls of grey matter swelled to entrails, they curled round one another like muscular snakes, became vague and misty like the spiral nebulae on astronomical charts. . . . What went on in the inflated grey whorls? One knew everything about the far-away nebulae, but nothing about the whorls.”

—Arthur Koestler, Darkness at Noon, 1941.