勇气意味着站起来说话，勇气也意味着坐下来倾听。
Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen.
The purpose of abstraction is not to be vague, but to create a new semantic level in which one can be absolutely precise.
目的的概念在行为的科学解释中没有位置。
The only way to achieve the impossible is to believe it is possible.
The Moving Finger writes; and, having writ, Moves on: nor all thy Piety nor Wit Shall lure it back to cancel half a Line, Nor all thy Tears wash out a Word of it.
True leadership means making tough decisions today that will benefit future generations.
The forest doesn't need us, but we need the forest—our survival depends on it.