Many people know how to work hard; many others know how to play well; but the rarest talent in the world is the ability to introduce elements of playfulness into work, and to put some constructive labor into our leisure.

Nice things are done for our own sake, not for the sake of others. The pleasure must reside in the performance, not in the applause. Good deeds are, in a deeper psychological way, a favor to oneself. If this is not grasped, then our whole sense of personal relationships becomes warped.

The pessimist sees only the tunnel; the optimist sees the light at the end of the tunnel; the realist sees the tunnel and the light - and the next tunnel.

The real danger is not that computers will begin to think like men, but that men will begin to think like computers.

No one should pay attention to a man delivering a lecture or a sermon on his "philosophy of life" until we know exactly how he treats his wife, his children, his neighbors, his friends, his subordinates and his enemies.

An idealist believes the short run doesn't count. A cynic believes the long run doesn't matter. A realist believes that what is done or left undone in the short run determines the long run.

When we have "second thoughts" about something, our first thoughts don't seem like thoughts at all - just feelings.