You can't climb up to the second floor without a ladder. When you set your aim too high and don't fulfill it, then your enthusiasm turns to bitterness. Try for a goal that's reasonable, and then gradually raise it.

To boast of a performance which I cannot beat is merely stupid vanity. And if I can beat it that means there is nothing special about it. What has passed is already finished with. What I find more interesting is what is still to come.

When I was young, I was too slow. I thought I must learn to run fast by practicing to run fast, so I ran 100 meters fast 20 times. Then I came back, slow, slow, slow.

The athlete of today is not an athlete alone. He's the center of a team - doctors, scientists, coaches, agents and so on.

Love and esteem are the first principles of friendship; it is always imperfect if either of these two are wanting.

Psychology, unlike chemistry, unlike algebra, unlike literature, is an owner's manual for your own mind. It's a guide to life. What could be more important than grounding young people in the scientific information that they need to live happy, healthy, productive lives? To have good relationships?

It is impossible to preserve my friendship with people who are allegedly leaders when they are attacking their own people, shooting at them, using tanks and other forms of heavy weaponry.

The relationships that people have - that are sexual, psychological, emotional - these relationships are not open to supervision by parents, schools, churches, or government. Nobody has any right to intervene at all in any kind of relationship like that.