"A man who is righteous only slaughters dogs, but a man who is unfaithful is mostly a scholar" comes from a poem by Cao Xuequan (1574-1646), an official and scholar in the Ming Dynasty. The full text is "Flies camp and dogs are greedy and greedy, how can apes bow again?" Those who are righteous are only those who slaughter dogs, but those who are unfaithful are mostly scholars." What this means is that those who talk about loyalty are mostly illiterate lower-class people and reckless people who work in humble professions, while knowledgeable and educated scholars often do treacherous and confusing things to their friends and lovers. Not to mention being brave enough to help strangers. "Dog butchers" are people who kill dogs and sell their meat as a profession. They generally refer to people who engage in menial professions.