Research has shown that a tired mind is often a more creative mind. It may sound counter-intuitive, but early birds should try solving problems late at night, while night owls should attempt to come up with solutions early in the morning.
It wasn’t people selling candles who invented the light bulb. If you want a paradigm shift, you need someone who comes from the outside.
Einstein would work hard on a problem for a couple of hours and then stop to play the violin. Playing a piece he knew well would require little conscious effort, allowing his mind to wander and ideas to arise.
By his account, ‘The theory of relativity occurred to me by intuition, and music is the driving force…’