Ash'arism (; Arabic: الأشعرية, romanized: al-ʾAshʿariyya) is one of the main Sunnī schools of Islamic theology (those being, Ashʿarism, Maturudism, and Atharism), founded by the Arab Muslim scholar, Shāfiʿī jurist, reformer (mujaddid), and scholastic theologian Abū al-Ḥasan al-Ashʿarī in the 9th–10th century. It established an orthodox guideline, based on scriptural authority, rationality, and theological rationalism.Al-Ashʿarī established a middle way between the doctrines of the Atharī and Muʿtazila schools of Islamic theology, based both on reliance on the sacred scriptures of Islam and theological rationalism concerning the agency and attributes of God. Ashʿarism eventually became the predominant school of theological thought within Sunnī Islam, and is regarded as the single most important school of Islamic theology in the history of Islam.The disciples of the Ashʿarī school are known as Ashʿarites, and the school is also referred to as the Ashʿarite school, which became one of the dominant theological schools within Sunnī Islam. Ashʿarī theology is considered one of the orthodox creeds of Sunnī Islam, alongside the Atharī and Māturīdī. Amongst the most famous Ashʿarite theologians are Imam Nawawi, Ibn Hajar al-Asqalani, Ibn al-Jawzi, al-Ghazali, al-Suyuti, Izz al-Din ibn 'Abd al-Salam, Fakhr al-Din al-Razi, Ibn 'Asakir, al-Subki, al-Taftazani, al-Baqillani and al-Bayhaqi. Scholars and scientists who were affiliated with the Ash'ari school included Al-Biruni, Ibn al-Haytham, Ibn al-Nafis, Ibn Battuta, and Ibn Khaldun. Source: Wikipedia (en)