Al-Shaykh Al-Tusi, also known as Abu Ja'far Muhammad ibn al-Hasan al-Tusi, was a prominent Shia Islamic scholar born in 995 CE in Tus, Iran. He is best known for his contributions to Islamic jurisprudence, theology, and philosophy. His works, including the influential Al-Tahdhib and Al-Istibsar, are foundational texts in Shia scholarship. Al-Tusi played a significant role in the development of the Shia religious tradition, particularly during the Buyid period. He also established the Najaf seminary, which became a major center for Shia learning. His legacy continues to influence Shia thought and education today.