岁不寒，无以知松柏；事不难，无以知君子无日不在是。
时节不寒冷，就不会知道松柏挺拔且郁郁葱葱的；事情不危难，就不会知道君子每日都在持守信念。
In dreams, you don't need to make any distinctions between things. Not at all. Boundaries don't exist. So in dreams there are hardly ever collisions.
衡量一个文明的标准是它如何对待其最弱的成员。