I was asked to act when I couldn’t act. I was asked to sing ’Funny Face’ when I couldn’t sing, and dance with Fred Astaire when I couldn’t dance - and do all kinds of things I wasn’t prepared for. Then I tried like mad to cope with it.
Mathematics is not a deductive science—that's a cliché. When you try to prove a theorem, you don't just list the hypotheses and then start to reason. What you do is trial and error, experimentation, guesswork.