You have to be willing to sacrifice to get what you want or what you need.
凡是有不和的地方,我们要为和谐而努力;凡是有谬误的地方,我们要为真理而努力;凡是有疑虑的地方,我们要为信任而努力;凡是有绝望的地方,我们要为希望而努力。
The process of grouping, of organization, is not arbitrary but follows definite laws.