"When one cultivates to the utmost the principles of his nature, and exercises them on the principle of reciprocity, he is not far from the path. What you do not like when done to yourself, do not do to others."
Doctrine of the Mean 13:3
"Tsze-kung said, Suppose the case of a man extensively conferring benefits on the people, and able to assist all, what would you say of him? Might he be called perfectly virtuous? The Master said, Why speak only of virtue in connection with him? Must he not have the qualities of a sage? Even Yao and Shun were still solicitous about this. Now the man of perfect virtue, wishing to be established himself, seeks also to establish others; wishing to be enlarged himself, he seeks also to enlarge others. To be able to judge of others by what is nigh in ourselves;-this may be called the art of virtue."
Confucius (551-479 BC), Analects 6:30
"What a man dislikes in his superiors, let him not display in the treatment of his inferiors; what he dislikes in inferiors, let him not display in the service of his superiors; what he hates in those who are before him, let him not therewith precede those who are behind him; what he hates in those who are behind him, let him not therewith follow those who are before him; what he hates to receive on the right, let him not bestow on the left; what he hates to receive on the left, let him not bestow on the right : - this is what is called The principle with which, as with a measuring-square, to regulate one's conduct."