Any man who reads too much and uses his own brain too little falls into lazy habits of thinking.
It is better to know how to learn than to know.
Learn as though you would never be able to master it; hold it as though you would be in fear of losing it.
Reading without reflecting is like eating without digesting.
The more I read, the more I acquire, the more certain I am that I know nothing.
Physics is like sex: sure, it may give some practical results, but that's not why we do it.
The deepest sin against the human mind is to believe things without evidence.
He who would learn to fly one day must first learn to stand and walk and run and climb and dance; one cannot fly into flying.
Those who fail to learn the lessons of history are doomed to repeat them.
What we know is a drop, what we don't know is an ocean.
Science is a rising force, It is creating a new world about us. It needs to be watched and pressed into service, and in any case, it would be courting disaster to ignore it.
Opinion is the medium between knowledge and ignorance.
Many much-learned men have no intelligence.
The progressive development of man is vitally dependent on invention.
Knowledge is of two kinds. We know a subject ourselves, or we know where we can find information upon it.
The first principle is that you must not fool yourself and you are the easiest person to fool.
God created man in His own image, says the Bible; philosophers reverse the process: they create God in theirs.
What sculpture is to a block of marble, education is to a human soul.
Medicine is my lawful wife and literature my mistress; when I get tired of one, I spend the night with the other.
There is nothing more notable in Socrates than that he found time, when he was an old man, to learn music and dancing, and thought it time well spent.
A little knowledge that acts is worth infinitely more than much knowledge that is idle.