数学不知道种族或地理界限;对于数学来说,文化世界是一个国家。
Every poem is a momentary stay against the confusion of the world.
君主所凭借着驱使臣下的,只有尚贤一种方法;臣下用来侍奉君主的,也只有仁义一条途径。 
True progress comes from challenging the status quo.