美玉和石块同匣并放，鱼眼和宝珠一起贯穿。劣马和骏马混杂不分，老牛驾辕，骏马两边。
实验中的每一次失败都是离成功更近的一步。
挑战让生活有趣，克服它们让生活有意义。
行为主义者问：为什么我们不把可观察的东西作为心理学的真正领域？
The security dilemma is a fundamental feature of international politics, as states' efforts to increase their own security often decrease the security of others.
"The only way to make sense out of change is to plunge into it, move with it, and join the dance."