What does the crow mean by laughing at pig black?

Crow joked that pig black is a two-part allegorical saying, which means pot calling the kettle black. It means that people should not only see the shortcomings of others, but also see their own shortcomings. Crows and pigs are black, so they are all black. Crows laugh at pig black, each other, one is darker than the other, which means two people with the same shortcomings, but one person laughs at the shortcomings of the other. From an objective point of view, they are almost the same, so such mutual ridicule is very funny. In a word, they have the same shortcomings, at least in some features. When these similarities are just used to describe each other, they can be described as ironic and black allegorical. Crow (scientific name: Corvussp. ) is the common name of several black birds of the genus Ophiuchus, whose feathers or most of them are dark and about 50 cm long.