There is one quality which one must possess to win, and that is definiteness of purpose, the knowledge of what one wants, and a burning desire to possess it.

I do not know how to teach philosophy without becoming a disturber of the peace.

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.

Just when I thought there wasn't room enough for another thought in my head, I had this great idea.

What is freedom of expression? Without the freedom to offend, it ceases to exist.

The first principle is that you must not fool yourself and you are the easiest person to fool.

You can never learn less, you can only learn more.

Necessity is the mother of invention.

The man who does not read good books has no advantage over the man who can't read them.

Knowledge is power. Information is liberating. Education is the premise of progress, in every society, in every family.

I prefer the company of peasants because they have not been educated sufficiently to reason incorrectly.

Although modesty is natural to man, it is not natural to children. Modesty only begins with the knowledge of evil.

All sciences are vain and full of errors that are not born of Experience, the mother of all Knowledge.

Books! I dunno if I ever told you this, but books are the greatest gift one person can give another.

My weapon is literature

In mathematics you don't understand things. You just get used to them.

I think that kids have a greater capacity for processing things than we give them credit for.

It isn't what we don't know that gives us trouble, it's what we know that ain't so.

Don't worry that children never listen to you; worry that they are always watching you.

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.

Learning never exhausts the mind.