数学的本质不是把简单的事情复杂化，而是把复杂的事情简单化。
The essence of mathematics is not to make simple things complicated, but to make complicated things simple.
The ultimate measure of a man is not where he stands in moments of comfort and convenience， but where he stands at times of challenge and controversy.
Without magic, there is no art. Without art, there is no idealism. Without idealism, there is no integrity. Without integrity, there is nothing but production.