曾子曰：「吾日三省吾身：為人謀，而不忠乎？與朋友交，而不信乎？傳，不習乎？」

Tseng-tzu
said, 〝I
examine myself thrice a day: Am I faithful in planning with others?
Am I trustworthy in dealing with friends? Haven't I reviewed the
lessons already learned?〞