If you spend too much time thinking about a thing, you'll never get it done.

I cannot teach anybody anything, I can only make them think.

To study and not think is a waste. To think and not study is dangerous.

The whole of science is nothing more than a refinement of everyday thinking.

Reading, after a certain age, diverts the mind too much from its creative pursuits. Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.

If you think a thing is impossible, you'll make it impossible.

If everybody is thinking alike, then somebody isn't thinking.

He who thinks little, errs much.

A public-opinion poll is no substitute for thought.

Character is higher than intellect...A great soul will be strong to live, as well as strong to think.

Thinking is the hardest work there is, which is probably the reason why so few engage in it.

To know what people really think, pay regard to what they do, rather than what they say.

I think, therefore I am.

The universe is a lot more complicated than you might think even if you start from a position of thinking that its pretty damn complicated to begin with.

"Why do you need to think? Can't we just sit and go budumbudumbudum with our lips for a bit?"

Success treads on every right step. For the instinct is sure, that prompts him to tell his brother what he thinks. He then learns, that in going down into the secrets of his own mind, he has descended into the secrets of all minds. He learns that he who has mastered any law in his private thoughts, is master to that extent of all men whose language he speaks, and of all into whose language his own can be translated.

I do not paint the things I see, I paint what I think.

Anyone who has ever looked into the glazed eyes of a soldier dying on the battlefield will think hard before starting a war.

Writing, to me, is simply thinking through my fingers.

We begin to think cosmically.

The scientists from Franklin to Morse were clear thinkers and did not produce erroneous theories. The scientists of today think deeply instead of clearly. One must be sane to think clearly, but one can think deeply and be quite insane.

Thinking too little about things or thinking too much both make us obstinate and fanatical.

Don't think about what you've left behind.

I never looked at the consequences of missing a big shot…when you think about the consequences you always think of a negative result.

At 7 a.m. all my voices start talking inside my head, and when it reaches a certain pitch I jump out and trap them before they're gone. Or I shower and then the voices talk. You solve problems not by thinking directly of them but allowing them to ferment in their own time.