Regret for the things we did can be tempered by time; it is regret for the things we did not do that is inconsolable.

Enemies, as well as lovers, come to resemble each other over a period of time.

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

What is much harder to handle is the sense that you have to live up to the mark someone else has set for you. The grades become too important, the competition too frantic, the fear of disappointing those who believe in you turns into an overwhelming nightmare.

Those obsessed with health are not healthy; the first requisite of good health is a certain calculated carelessness about oneself.

Good teaching must be slow enough so that it is not confusing, and fast enough so that it is not boring.

The difference between faith and superstition is that the first uses reason to go as far as it can, and then makes the jump; the second shuns reason entirely — which is why superstition is not the ally, but the enemy, of true religion.