Thinking is the activity I love best, and writing to me is simply thinking through my fingers. I can write up to 18 hours a day. Typing 90 words a minute, I’ve done better than 50 pages a day. Nothing interferes with my concentration. You could put an orgy in my office and I wouldn’t look up — well, maybe once or twice.

Isaac Asimov (1920-1992) Russian-American author, polymath, biochemist

(Attributed)