Whether a man can excommunicate himself, his equal, or his superior?

❌ Objection 1 : It would seem that a man can excommunicate himself, his equal, or his superior. For an angel of God was greater than Paul, according to Mt. 11:11: "He that is lesser in the kingdom of heaven is greater then he, a greater" than whom "hath not risen among men that are born of women." Now Paul excommunicated an angel from heaven (Gal. 1:8). Therefore a man can excommunicate his superior.

❌ Objection 2 : Further, sometimes a priest pronounces a general excommunication for theft or the like. But it might happen that he, or his equal, or a superior has done such things. Therefore a man can excommunicate himself, his equal, or a superior.

❌ Objection 3 : Further, a man can absolve his superior or his equal in the tribunal of Penance, as when a bishop confesses to his subject, or one priest confesses venial sins to another. Therefore it seems that a man may also excommunicate his superior, or his equal.