The past is not dead, it is not even past.
过去并未死去，它甚至还未过去。
Happiness is not the belief that we don't need to change; it is the realization that we can.
Science thrives on doubt and skepticism.
"The best books are the ones that leave you a little different than when you started."
Every mathematical problem is a puzzle waiting to be solved, and every solution is a step towards greater understanding.