矛

spear / lance / pike

ancient spear-like weapon 18 Chinese feet 尺[chi3] in length, with a wavy spearhead like a snake's body

internal contradiction among the people (pretext for a purge)

lit. use sb's spear to attack his shield (idiom, derived from Han Feizi 韓非子|韩非子); turning a weapon against its owner / fig. to attack an opponent using his own devices / hoist with his own petard

internal contradiction

contradictions between ourselves and the enemy / Either you are for us or against us.

On the correct handling of internal contradictions among the people, Mao Zedong's tract of 1957

(bird species of China) lanceolated warbler (Locustella lanceolata)

shaft

(bird species of China) Chinese babax (Babax lanceolatus)

(bird species of China) gyrfalcon (Falco rusticolus)