Today, all physicists know from studying Einstein and Bohr that sometimes an idea which looks completely paradoxical at first, if analyzed to completion in all detail and in experimental situations, may, in fact, not be paradoxical.Richard Feynman
The situation in the sciences is this: A concept or an idea which cannot be measured or cannot be referred directly to experiment may or may not be useful. It need not exist in a theory.Richard Feynman
Often one postulates that a priori, all states are equally probable. This is not true in the world as we see it. This world is not correctly described by the physics which assumes this postulate.Richard Feynman
It has not yet become obvious to me that there's no real problem. I cannot define the real problem; therefore, I suspect there's no real problem, but I'm not sure there's no real problem.Richard Feynman
Anyone who conducts an argument by appealing to authority is not using his intelligence; he is just using his memory.Leonardo da Vinci
Although nature commences with reason and ends in experience it is necessary for us to do the opposite, that is to commence with experience and from this to proceed to investigate the reason.Leonardo da Vinci
Experience never errs; it is only your judgments that err by promising themselves effects such as are not caused by your experiments.Leonardo da Vinci
Nothing in all the world is more dangerous than sincere ignorance and conscientious stupidity.Martin Luther King Jr.
It is reasonable that forces directed toward bodies depend on the nature and the quantity of matter of such bodies, as happens in the case of magnetic bodies.Isaac Newton
