Let us not negotiate out of fear, but let us never fear to negotiate.

Once you say you’re going to settle for second, that’s what happens to you in life, I find.

As we express our gratitude, we must never forget that the highest appreciation is not to utter words, but to live by them.

I look forward to an America which will not be afraid of grace and beauty.

When we got into office, the thing that surprised me the most was that things were as bad as we'd been saying they were.

We choose to go to the moon, not because it's easy but because it's hard.

We must use time as a tool, not as a couch.

Too often we... enjoy the comfort of opinion without the discomfort of thought.

All this will not be finished in the first one hundred days, nor will it be finished in the first one thousand days, nor in the life of this administration, nor even perhaps in our lifetime on this planet. But let us begin.

Peace in space will help us nought once peace on earth is gone.

What really counts is not the immediate act of courage or of valor, but those who bear the struggle day in and day out.

This country cannot afford to be materially rich and spiritually poor.

When written in Chinese, the word crisis is composed of two characters. One represents danger, and the other represents opportunity.

The goal of education is the advancement of knowledge and the dissemination of truth.

Victory has a hundred fathers, and defeat is an orphan.

Change is the law of life. And those who look only to the past or the present are certain to miss the future.

Let both sides seek to invoke the wonders of science instead of its terrors.