人类需要悲伤,正如需要欢乐一样。
The only way to be free is to constantly challenge authority and convention.
In the long history of humankind (and animal kind, too) those who learned to collaborate and improvise most effectively have prevailed.  
仲弓问仁。孔子说:“出门时要象会见贵宾一样庄重,建工程时要象举行盛大祭典一样严肃。自己不愿做的,不要强加于人。同事中相处融洽,亲属中和睦友爱。”仲弓说:“我虽不才,愿照此办理。”
在科学中,最令人兴奋的短语不是"我发现了!"而是"这有点奇怪..."