I have sought love, first, because it brings ecstasy – ecstasy so great that I would often have sacrificed all the rest of life for a few hours of that joy. ... I have sought it, finally, because in the union of love I have seen, in a mystic miniature, the prefiguring vision of the heaven that saints and poets have imagined.

To be able to fill leisure intelligently is the last product of civilization, and at present very few people have reached this level.

The whiter my hair becomes, the more ready people are to believe what I say.

But if thought is to become the possession of many, not the privilege of the few, we must have done with fear. It is fear that holds men back - fear lest their cherished beliefs should prove delusions, fear lest the institutions by which they live should prove harmful, fear lest they themselves should prove less worthy of respect than they have supposed themselves to be.

The evolution of our spirit is blazed on the dark background of eternity by our individual wakes. Every person can, if he/she wishes, leave a more or less brilliant wake behind them.

Most people believe in God because they have been taught from early infancy to do it, and that is the main reason. Then I think that the next most powerful reason is the wish for safety.

At first it seems obvious, but the more you think about it the stranger the deductions from this axiom seem to become; in the end you cease to understand what is meant by it.