Bronowski, Jacob There never was a great scientist who did not make bold guesses, and there never was a bold man whose guesses were not sometimes wild.
Feynman, Richard In general we look for a new law by the following process. First we guess it. Then we compute the consequences of the guess to see what would be implied if this law that we guessed is right. Then we compare the results of the computation to nature, with experiment or experience, compare it directlywith observation, to see if it works. If it disagreeswith experiment it’s wrong. In that simple statement is the key to science. It does not make any difference how beautiful your guess is. It does not make any difference how smart you are, who made the guess, or what his name isif it disagrees with experiment it’s wrong. That is all there is to it.