The world is my country, all mankind are my brethren, and to do good is my religion.

Every failed experiment is a step closer to success, as long as you learn from it.

When you're young you think you're going to have lots of friends. But as you get older, you realize you can count them on one hand.

【解释】幸福不可强求，保持愉快的心情，更能感受到幸福；灾祸难以避免，消除怨恨他人的念头，就能远离灾祸。