Sun Bin's Mutilation by Pang Juan

Sun Bin and Pang Juan studied military strategy together. Later, Pang Juan became a general in Wei. Jealous of Sun Bin's superior talent, he lured Sun to Wei under false pretenses, then framed him for treason. Sun Bin was convicted and sentenced to the "Bin" punishment—removal of his kneecaps—and facial tattooing, leaving him permanently disabled. To survive, Sun Bin feigned madness. He eventually escaped to the Qi state with the aid of envoys, where he served as military strategist. During the Battle of Maling, Sun Bin orchestrated an ambush that defeated Pang Juan, leading to Pang's suicide. This case epitomizes a vicious betrayal among fellow disciples driven by envy.

Sun Bin was convicted and mutilated in Wei. No formal judicial reversal occurred, but history vindicated him. He escaped to Qi, achieved military triumph, and Pang Juan met his death in battle.

The central dispute is whether Pang Juan fabricated the treason charges purely out of jealousy, making the conviction and mutilation a miscarriage of justice, and whether such bodily punishment was legally and morally justified.

The story became a lasting cautionary tale about envy and treachery. Sun Bin authored "Sun Bin's Art of War," enriching Chinese military thought. It cemented cultural motifs of perseverance under injustice and eventual retribution.