A thought which does not result in an action is nothing much, and an action which does not proceed from a thought is nothing at all.

It is not length of life, but depth of life. The way to make life worth living is not to guard the hours, but to fill them — not to preserve the days, but to use them.

It is not enough to be busy; so are the ants. The question is: what are we busy about?

The mind is furnished with a set of instincts which seek out certain kinds of things in the world—food, safety, beauty, knowledge—and the universe cooperates by containing those things. But there are other things in the universe that do not call to any instinct, that have no utility, that simply exist in their own right.