‘Well, do you know the one,’ I began, ‘in which two geologists converse in a cafe? One of them says: ‘Yes, unfortunately fifteen billion years from now the Sun will cool, and then all life on Earth will perish.’ A card-player nearby has been half listening to the joke, and turns in terror to the geologist: ‘What did you say? In how many years will the Sun cool?’ ‘Fifteen billion years,’ the scientist replies. The card-player lets out a sigh of relief: ‘Oh, I was afraid you said fifteen million!’

— László Feleki in Impact of Science on Society, 1969