Rule of 7 in research. You can find out anything if you are willing to go seven levels. If the first source you ask doesn’t know， ask them who you should ask next， and so on down the line. If you are willing to go to the 7th source， you’ll almost always get your answer.

你必须愿意失败，愿意犯错，并不断尝试。

解释：受宠而不骄横，骄横而能安于下位，地位在下而不怨恨，怨恨而能克制的人，是非常少见。