Who are the Mu'tazilah and why were they given that name?

Question:
May Allah reward you. The questioner asks: Who are the Mu'tazilah? And why were they given that name?

Answer:
The Mu'tazilah are the followers of Wasil ibn 'Ata, a student of al-Hasan al-Basri. He was one of the students of al-Hasan al-Basri (may Allah have mercy on him), the imam of the Tabi'un. When al-Hasan al-Basri was asked about the one who commits a major sin—whether he is a disbeliever or a believer—he said (may Allah have mercy on him): "The one who commits a major sin is an open sinner, not a disbeliever. He is a believer, but his faith is deficient. His faith is deficient, but he is not a disbeliever." Wasil ibn 'Ata, his student, said: "As for me, I say he is neither a Muslim nor a disbeliever. He is in the intermediate position between the two positions."
So he introduced this school of thought: the intermediate position between the two positions—neither a Muslim nor a disbeliever. He is here one of the creation, neither a Muslim nor a disbeliever.
It is necessary that he be either a Muslim or a disbeliever. A Muslim may have deficient faith or complete faith. So he withdrew from al-Hasan's gathering, and his followers joined him. They were called the Mu'tazilah because they withdrew from al-Hasan al-Basri's gathering. Yes.