The security dilemma is a fundamental feature of international politics, as states' efforts to increase their own security often decrease the security of others.

You can't let praise or criticism get to you. It's a weakness to get caught up in either one.

每本书都是一次旅程，每次旅程都是一本书。

成功不仅仅由利润衡量，而是由我们创造的积极影响来衡量。

Sustainability isn't an option; it's our responsibility to future generations.