I felt that I had to write. Even if I had never been published, I knew that I would go on writing, enjoying it and experiencing the challenge.

If you're successful in what you do over a period of time, you'll start approaching records, but that's not what you're playing for. You're playing to challenge and be challenged.

You can't be afraid to make errors! You can't be afraid to be naked before the crowd, because no one can ever master the game of baseball, or conquer it. You can only challenge it.

But it is a delightful challenge to try to depict interesting aliens.

I love a challenge and the last four years it has all come to fruition and it has been wonderful.

There is no greater challenge than to have someone relying upon you; no greater satisfaction than to vindicate his expectation.

In 1995, I founded The Molecular Sciences Institute with a gift from the Philip Morris Company where I hoped that we could create an environment where young people could pursue science in an atmosphere of harmonious purpose and high intellectual challenge.

I'm used to people not paying me a whole lot of attention and underestimating me and, frankly, for me a big challenge is to have people believe that I can be the president of the United States.

And obviously, from our own personal point of view, the principal challenge is a personal challenge.

What we can do now is contribute to a clearer understanding of what happened that day on Everest in the hope that the lessons to be learned will reduce the risk for others who, like us, take on the challenge of the mountains.

You can't be suspicious of a tree, or accuse a bird or a squirrel of subversion or challenge the ideology of a violet.

How many Catholic schools do you think teach the students to question the authority of the Pope? Do you believe Christian schools teach students to question or challenge the authority of Jesus Christ? Do military schools teach the cadets to challenge the authority.

This film, Tomb Raider 2, is a big challenge. It's quite exhausting.

The United States did not choose to fight Islamic extremists. These terrorists chose to fight our way of life. They chose to challenge our existence.

It was quite a challenge to make people eat crab ice cream.