单子是不可分割的实体，是构成世界的基本元素。
Monads are indivisible entities, the basic elements that constitute the world.
The study of black holes has revolutionized our understanding of space and time.
【译文】 孔子说：“不怕没人了解自己，就怕自己不了解别人。”
What you actually pay for something is at least twice the listed price because of the energy， time， money needed to set it up， learn， maintain， repair， and dispose of at the end. Not all prices appear on labels. Actual costs are 2x listed prices.
孔子说：“不怕没人了解自己，就怕自己没有能力。”