The greatest obstacle to being heroic is the doubt whether one may not be going to prove one's self a fool; the truest heroism is to resist the doubt, and the profoundest wisdom to know when it ought to be resisted, and when it be obeyed.

Always be learning. The world changes fast, and you need to keep up.

传记的挑战不在于发现事实 - 而在于发现事实背后的意义。