Never, never, never give up.

Knowledge is knowing that we cannot know.

Experience without theory is blind, but theory without experience is mere intellectual play.

Positive thinking will let you do everything better than negative thinking will.

Be miserable. Or motivate yourself. Whatever has to be done, it's always your choice.

Optimism is the faith that leads to achievement. Nothing can be done without hope and confidence.

Strong and bitter words indicate a weak cause.

Perhaps I am stronger than I think.

There is little that can withstand a man who can conquer himself.

Out of suffering have emerged the strongest souls; the most massive characters are seared with scars.