We need to accept that we won't always make the right decisions, that we'll screw up royally sometimes—understanding that failure is not the opposite of success, it's part of success.

Fearlessness is not the absence of fear. It's the mastery of fear. It's about getting up one more time than we fall down.

If there is no struggle, there is no progress.

The man who will get up will be helped up; and the man who will not get up will be allowed to stay down.

A gem cannot be polished without friction, nor a man perfected without trials.

Theoretical physics is one of the few fields in which being disabled is no handicap - it is all in the mind.

I might have to stumble a little bit more in public than others, but that's fine, I don't mind, I've developed a thick skin.

Difficulties are things that show a person what they are.

Good planning is important. I've also regarded a sense of humor as one of the most important things on a big expedition. When you're in a difficult or dangerous situation, or when you're depressed about the chances of success, someone who can make you laugh eases the tension.

Advance, and never halt, for advancing is perfection. Advance and do not fear the thorns in the path, for they draw only corrupt blood.

I have frequently noticed how circumstances conspire to help a man, or a boy, when he has thoroughly resolved on doing a thing.

When facing a difficult task, act as though it is impossible to fail. If you are going after Moby Dick, take along the tartar sauce.