All the problems of the world could be settled if people were only willing to think. The trouble is that people very often resort to all sorts of devices in order not to think, because thinking is such hard work

If you think you can, you can. And if you think you can't, you're right

I always feel sorry for people who think more about a rainy day ahead than sunshine today

To get others to come into our ways of thinking, we must go over to theirs; and it is necessary to follow, in order to lead

The best thinking has been done in solitude. The worst has been done in turmoil

It's interesting to think that my ancestors used to live in the trees, like apes, until finally they got the nerve to head out onto the plains, where some were probably hit by cars

People think of the inventor as a screwball, but no one ever asks the inventor what he thinks of other people

The trouble with most people is that they think with their hopes or fears or wishes rather than with their minds

People who bite the hand that feeds them usually lick the boot that kicks them

Thinking is one thing no one has ever been able to tax