Via The Guardian:
Where and when do you do your best thinking?
DA: I've no idea. All I know is if I'm stuck with something and go to bed, I wake up with the answer.
RD: That's a fascinating phenomenon, isn't it?
DA: That's if I find the answer at all.
RD: Very few people say, "I think I'll have an hour's thinking now."
DA: Mathematicians do. I had an uncle who was a mathematician, and one of his students said, "How long can you think for?" He said, "I sometimes manage two or three minutes." And this young man said, "I've never managed more than 90 seconds." Of course, that's abstract thinking, and by and large I'm not an abstract thinker.
