Mencius - Book 4, Part 2, Chapter 33A

A man of Ch'î had a wife and a concubine, and lived together with them in his house. When their husband went out, he would get himself well filled with wine and flesh, and then return, and, on his wife's asking him with whom he ate and drank, they were sure to be all wealthy and honorable people.

The wife informed the concubine, saying, 'When our good man goes out, he is sure to come back having partaken plentifully of wine and flesh. I asked with whom he ate and drank, and they are all, it seems, wealthy and honorable people. And yet no people of distinction ever come here. I will spy out where our good man goes.'

Accordingly, she got up early in the morning, and privately followed wherever her husband went.
~ James Legge translation via nothingistic.org ~

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