I believe that to solve any problem that has never been solved before, you have to leave the door to the unknown ajar. - Richard Feynman

Doubting the great Descartes ... was a reaction I learned from my father: Have no respect whatsoever for authority; forget who said it and instead look what he starts with, where he ends up, and ask yourself, "Is it reasonable?"

Professor Feynman?” “Hey! Why are you bothering me at this time in the morning?” “I thought you’d like to know that you’ve won the Nobel Prize.” “Yeah, but I’m sleeping! It would have been better if you had called me in the morning.” — and I hung up.

What do we mean by “understanding” something? We can imagine that this complicated array of moving things which constitutes “the world” is something like a great chess game being played by the gods, and we are observers of the game. We do not know what the rules of the game are; all we are allowed to do is to watch the playing. Of course, if we watch long enough, we may eventually catch on to a few of the rules. The rules of the game are what we mean by fundamental physics. Even if we knew every rule, however, we might not be able to understand why a particular move is made in the game, merely because it is too complicated and our minds are limited. If you play chess you must know that it is easy to learn all the rules, and yet it is often very hard to select the best move or to understand why a player moves as he does. So it is in nature, only much more so.