The function of socialism is to raise suffering to a higher level.

The most beautiful people we have known are those who have known defeat, known suffering, known struggle, known loss, and have found their way out of the depths.

I have called this principle, by which each slight variation, if useful, is preserved, by the term Natural Selection.  

自信来自于准备充分并精通自己的领域。

生活中最大的荣耀不在于从不跌倒，而在于每次跌倒后都能站起来。

You have to keep thinking about what you can do to make the world a better place.

数学的真正力量在于它简化复杂事物的能力，使不可理解的事物变得可理解。