Baha al-Din al-Amili

Baha al-Din al-Amili (Arabic: بهاء الدين العاملي; Persian: بهاءالدین عاملی: 18 February 1547 – 1 September 1621), commonly known as Sheikh Bahāʾī, was a Twelver Shia Muslim scholar and polymath in Safavid Iran, who composed various works in Arabic and Persian. Closely tied to the court of Shah Abbas the Great, he became known for his role in the intellectual sphere of Isfahan and is seen as a leading figure in his field, with seventy-seven scholars counted among his students. An ethnic Arab, he was originally from Jabal Amil (present-day south Lebanon) in Ottoman Syria. During his childhood, his family moved to Iran, where his father Husayn ibn Abd al-Samad became the shaykh al-Islam in Herat under Tahmasp I.

He stands out as one of the most influential Arab figures, and figures generally, in shaping the scientific, cultural, urban, and intellectual identity of Safavid Iran. He was the principal planner and architectural mind behind the transformation of Safavid Isfahan, credited with devising the overall spatial logic and ceremonial symbolism of the imperial capital. Sheikh Bahāʾī conceived the urban vision behind Naqsh-e Jahan Square and was instrumental in initiating the planning of the Shah Mosque, Sheikh Lotfollah Mosque, and Ali Qapu Palace. His designs also structured the layout of the Imperial Bazaar and he is also associated with hydraulic innovations and water management projects, though attributions such as the Zarrīn Kamar canal remain speculative. He served as a leading religious scholar in the Imam Reza Shrine, taught Islamic sciences, and contributed to the administration of its religious affairs. He is buried in the shrine.

As chief advisor to Abbas the Great, Sheikh Bahāʾī played a central role in defining the symbolic and geometric principles of Safavid civic and religious architecture. His commanding intellectual leadership and cohesive vision, executed through close collaboration with master builders and artisans, were instrumental in forging the Safavid architectural identity. A prolific author in both Arabic and Persian, Sheikh Bahaʾī composed over one hundred treatises spanning jurisprudence, logic, astronomy, mathematics, and theology—primarily in his mother tongue, Arabic. His contributions also extended to literature and poetry, including didactic and mystical verse in Persian. In his Persian work Tashrīḥ al-Aflāk, he was among the earliest Muslim thinkers to propose the possibility of the Earth’s motion, anticipating the later diffusion of Copernican ideas in the Islamic world.