When someone tells you about the peak year of human history， the period of time when things were good before things went downhill， it will always be the years of when they were 10 years sold — which is the peak of any human’s existence.

Beauty comes from the way things are used, not just from their appearance.

The true power of mathematics is not in its complexity, but in its simplicity and elegance.

人真正的祖国是童年。