Analects 2.17

The Master said, "Yu, shall I teach you what knowledge is? When you know a thing, to hold that you know it; and when you do not know a thing, to allow that you do not know it;—this is knowledge."

1. Tsze-chang was learning with a view to official emolument.

2. The Master said, "Hear much and put aside the points of which you stand in doubt, while you speak cautiously at the same time of the others:—then you will afford few occasions for blame. See much and put aside the things which seem perilous, while you are cautious at the same time in carrying the others into practice:—then you will have few occasions for repentance. When one gives few occasions for blame in his words, and few occasions for repentance in his conduct, he is in the way to get emolument."