Don't let fear stop you from doing what you want to do.
The art of teaching is the art of assisting discovery.
刚强纯洁的高尚人品，要在烈火般艰苦的斗争中锤炼；惊天动地的丰功伟业，必须在薄冰般险恶的环境里前进。
事实上，自然科学长期以来只是大脑和想象力的产物：现在是时候回归到对物质和显而易见事物的朴素而健全的观察了。