“You may be disappointed if you fail, but you are doomed if you don't try.”

“Try, reach, want, and you may fall. But even if you do, you might be okay anyway.
If you don't try, you save nothing, because you might as well be dead.”

“You never fail until you stop trying.”

“If you try to be anyone but yourself, you will fail; if you are not true to your own heart, you will fail. Then again, there's no success like failure”

“It takes a certain amount of courage to tackle very hard problems in science, I now realise. You don't know what the timescale of your work will be: decades or only a few years. Or your approach may be fatally flawed and doomed to fail. Or you could get scooped just as you are finalising your work. It is very stressful.”

“If you try to fail, and succeed, which have you done?”

“Don't expect much and you won't be disappointed.”

“Don't feel bad when you meet disappointment, it prepares you for an extraordinary ending”

“Try them, try them, and you may! Try them and you may, I say.”

“Try as you may, you don't get down as you would from a horse, you get down as you would from a house afire. You make a spectacle of yourself every time.”