Aside from his musical genius, Mingus was psychologically unstable. He was convicted for assault, and spent some time in the Bellevue locked ward.

During the making of The Black Saint and The Sinner Lady, Mingus was displeased with the pianist (Jaki Byard). Byard asked Mingus to 'show him or play it himself'. The two first piano solos are thus Mingus'. (Quite a humiliation for Byard).

Once, during a live performance, Mingus was so put out by the trumpeter's performance that he kicked him off stage. (Yes - literally kicked.)

He asked his psychologist, Edmund Pollock, Ph.D. to write a review on his above mentioned album, and he wrote "He feels intensively. He tries to tell people he is in great pain and anguish because he loves...His music is a call for acceptance, respect, love, understanding, fellowship, freedom..."