"The use of traveling is to regulate imagination by reality, and instead of thinking how things may be, to see them as they are."

The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.

无产阶级，现今社会的最下层，如果不炸毁构成官方社会的整个上层，就不能抬起头来，挺起胸来。