The reasoning is simple: In large households fish and pig raising are communal industries; domestic harmony increases production and wealth, while friction upsets the animals and leads to losses.
道理其實簡單：在大家庭裡，養魚飼豬是公產，各房和諧相處、同心協力，自然生機盎然，一片欣欣向榮；反之，兄弟鬩牆、妯娌反目，未免六畜不安，敗相畢露矣。