Among them are the Bāṭinīs, the Ismāʿīlīs, and others of the same stripe—such as Ibn Sīnā (Avicenna) and his ilk, the authors of the Epistles of the Brethren of Purity, and the ʿUbaydid rulers who once held power in Egypt from the Ḥākimiyyah faction and those like them. Outwardly they paraded as Shiʿites, but inwardly they were irreligious unbelievers. They are variously labeled the Qarmaṭians, the Bāṭinīs, and by other similar names.