Mencius - Book 4, Part 1, Chapter 4

Mencius said, 'If a man love others, and no responsive attachment is shown to him, let him turn inwards and examine his own benevolence. If he is trying to rule others, and his government is unsuccessful, let him turn inwards and examine his wisdom. If he treats others politely, and they do not return his politeness, let him turn inwards and examine his own feeling of respect.

'When we do not, by what we do, realize what we desire, we must turn inwards, and examine ourselves in every point. When a man's person is correct, the whole kingdom will turn to him with recognition and submission.

'It is said in the Book of Poetry,

"Be always studious to be in harmony with the ordinances of God,
And you will obtain much happiness."'

~ James Legge translation via nothingistic.org ~

Go here to read the introductory post to this serialized version of the Works of Mencius.