Give me a place to stand and I will move the earth.

Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.

The most beautiful thing we can experience is the mysterious. It is the source of all true art and science.

If A is success in life, then A equals x plus y plus z. Work is x; y is play; and z is keeping your mouth shut.

If we knew what it was we were doing, it would not be called research, would it?

I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones.

As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.

Real knowledge is to know the extent of one's ignorance.

A journey of a thousand miles begins with a single step.

By three methods we may learn wisdom: First, by reflection, which is noblest; Second, by imitation, which is easiest; and third by experience, which is the bitterest.

He who learns but does not think, is lost! He who thinks but does not learn is in great danger.

The only good is knowledge and the only evil is ignorance.