Mencius - Book 4, Part 2, Chapter 27

The officer Kung-hang having on hand the funeral of one of his sons, the Master of the Right went to condole with him. When this noble entered the door, some called him to them and spoke with him, and some went to his place and spoke with him.

Mencius did not speak with him, so that he was displeased, and said, 'All the gentlemen have spoken with me. There is only Mencius who does not speak to me, thereby slighting me.'

Mencius having heard of this remark, said, 'According to the prescribed rules, in the court, individuals may not change their places to speak with one another, nor may they pass from their ranks to bow to one another. I was wishing to observe this rule, and Tsze-âo understands it that I was slighting him: is not this strange?'
~ James Legge translation via nothingistic.org ~

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