As we acquire more knowledge, things do not become more comprehensible but more mysterious.
Knowledge becomes evil if the aim be not virtuous.
The progressive development of man is vitally dependent on invention.
Medicine is my lawful wife and literature my mistress; when I get tired of one, I spend the night with the other.
Common sense is the collection of prejudices acquired by age eighteen.
Just when I thought there wasn't room enough for another thought in my head, I had this great idea.
Learning never exhausts the mind.
A little knowledge that acts is worth infinitely more than much knowledge that is idle.
Imagination is more important than knowledge.
Opinion is the medium between knowledge and ignorance.
The man who does not read good books has no advantage over the man who can't read them.
The highest activity a human being can attain is learning for understanding, because to understand is to be free.
If you can't explain it simply, you don't understand it well enough.
It is beyond a doubt that all our knowledge begins with experience.
The books that the world calls immoral are books that show the world its own shame.
Necessity is the mother of invention.
All knowledge that the world has ever received comes from the mind; the infinite library of the universe is in our own mind.
What we know is a drop, what we don't know is an ocean.
I am indebted to my father for living, but to my teacher for living well.
I cannot teach anybody anything. I can only make them think
The whole of science is nothing more than a refinement of everyday thinking.