The development of formal systems has revolutionized our understanding of mathematics.

沟通“三”原则，要找到真相，让别人比他们之前说的更深一些，一次、两次、三次的重复这个过程，第三次你就接近真相了。

Inequality is not inevitable. It is a result of policy choices.

The end of history will be a very sad time. The struggle for recognition, the willingness to risk one's life for a purely abstract goal, the worldwide ideological struggle that called forth daring, courage, imagination, and idealism, will be replaced by economic calculation, the endless solving of technical problems, environmental concerns, and the satisfaction of sophisticated consumer demands.