Be brave, take risks, nothing can substitute experience.
勇敢一点，冒险一试，没有什么能替代经验。
The freedom of thought is the most precious freedom.
不要担心你在数学上遇到的困难；我敢保证我遇到的困难比你还大得多。
Do not fear to be eccentric in opinion， for every opinion now accepted was once eccentric.
"Every story is a journey, and every journey changes the traveler."
The present state of the system of nature is evidently a consequence of what it was in the preceding moment, and if we conceive of an intelligence which at a given instant comprehends all the relations of the entities of this universe, it could state the respective positions, motions, and general effects of all these entities at any time in the past or future.