My rule is, when you are unhappy, think about it. But when you're happy, don't. Why spoil it? You're probably happy for some ridiculous reason and you'd just spoil it to know it.

Experiment is the sole judge of the validity of any idea.

It is in the admission of ignorance and the admission of uncertainty that there is a hope for the continuous motion of human beings in some direction that doesn't get confined, permanently blocked, as it has so many times before in various periods in the history of man.

A great deal more is known than has been proved.

There are theoretical physicists who imagine, deduce, and guess at new laws, but do not experiment; and then there are experimental physicists who experiment, imagine, deduce, and guess.

Phenomena complex-laws simple....Know what to leave out.

What do I advise? Forget it all. Don't be afraid. Do what you get the most pleasure from. Is it to build a cloud chamber? Then go on doing things like that. Develop your talents wherever they may lead. Damn the torpedoes - full speed ahead!If you have any talent,or any occupation that delights you,do it, and do it to the hilt