Insight, untested and unsupported, is an uncertain guarantee of the truth.

The good life is one inspired by love and guided by knowledge.

The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.

The time you enjoy wasting is not wasted time.

Fear is the main source of superstition, and one of the main sources of cruelty. To conquer fear is the beginning of wisdom.

Men are born ignorant, not stupid. They are made stupid by education.

An Honest politician will not be tolerated by a democracy unless he is very stupid ... because only a very stupid man can honestly share the prejudices of more than half the nation.

If there were in the world today any large number of people who desired their own happiness more than they desired the unhappiness of others, we could have a paradise in a few years.

We have in fact, two kinds of morality, side by side: one which we preach, but do not practice, and another which we practice, but seldom preach.

The fact that an opinion has been widely held is no evidence whatever that it is not utterly absurd.

Cruel men believe in a cruel god and use their belief to excuse their cruelty. Only kindly men believe in a kindly god, and they would be kindly in any case.

By trying to grab fulfillment everywhere, we find it nowhere.

My attention was like cooking butter, not spreadable at the best of times. And when it was spreadable, it could destroy your toast by setting it ablaze. I was unpredictable, even to myself.

I only had three teachers, really, that were interesting, and all three of them were women.

Skill is the bridge between success and great success.

I hear the cheers when they roared and the jeers when they echoed.

Meidtation and selfless giving must always go together. They work together to create immortality.

Try not to have idols: they are interchangeable and lead to a wantonness that is easily mistaken for love.

At an Olympics Game, you want to enjoy it, especially if you know it's going to be your last one.

And indeed there will be time To wonder, "Do I dare?" and, "Do I dare?" Time to turn back and descend the stair, With a bald spot in the middle of my hair.

Cryptography has generated number theory, algebraic geometry over finite fields, algebra, combinatorics and computers.