To every action there is always an equal and opposite or contrary, reaction
If the facts don't fit the theory, change the facts.
Any sufficiently advanced technology is indistinguishable from magic.
Just because I don't care doesn't mean I don't understand.
I cannot live without books.
If you can't explain it simply, you don't understand it well enough.
Know what you are talking about.
Most people have never learned that one of the main aims in life is to enjoy it.
It is better to know how to learn than to know.
In order to stave off covetouness, greed, and spite, citizens world over must be educated.
No power and no treasure can outweigh the extension of our knowledge.
Books are as useful to a stupid person as a mirror is useful to a blind person.
If there were no bad people, there would be no good lawyers.
Learning never exhausts the mind.
Medicine is my lawful wife and literature my mistress; when I get tired of one, I spend the night with the other.
All knowledge that the world has ever received comes from the mind; the infinite library of the universe is in our own mind.
Education is the kindling of a flame, not the filling of a vessel.
I do not know how to teach philosophy without becoming a disturber of the peace.
If help and salvation are to come, they can only come from the children, for the children are the makers of men.
It isn't what we don't know that gives us trouble, it's what we know that ain't so.
One test of the correctness of educational procedure is the happiness of the child.