I am indebted to my father for living, but to my teacher for living well.
Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.
Those who fail to learn the lessons of history are doomed to repeat them.
All knowledge that the world has ever received comes from the mind; the infinite library of the universe is in our own mind.
If you can't explain it simply, you don't understand it well enough.
If I could explain it to the average person, I wouldn't have been worth the Nobel Prize.
I cannot live without books.
A little knowledge that acts is worth infinitely more than much knowledge that is idle.
Books are for people who wish they were somewhere else.
The progressive development of man is vitally dependent on invention.
If I have seen further it is by standing on the shoulders of Giants.
A thought is an idea in transit.
Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it.
The highest result of education is tolerance.
With educated people, I suppose, punctuation is a matter of rule; with me it is a matter of feeling. But I must say I have great respect for the semi-colon; it's a useful little chap.
Opinion is the medium between knowledge and ignorance.
Investigate, educate and organize.
Language is courage: the ability to conceive a thought, to speak it, and by doing so to make it true.
The real solution lies in a world in which charity will have become unnecessary.
I like poems you can tack all over with a hammer and there are no hollow places.
The fullness of knowledge only comes through the awareness of ignorance.