The most important political development of the last two centuries has been the rise of the modern state.

Technology in forestry has evolved from chainsaws to satellites, but our responsibility remains the same.

没有痛苦，就没有快乐。

"You can never know everything, and part of what you know is always wrong."

成功不在于你赚了多少钱，而在于你为别人的生活带来了什么改变。