Ṣadr ad-Dīn Muḥammad Shīrāzī, more commonly known as Mullā Ṣadrā, was a Persian Twelver Shi'i Islamic mystic, philosopher, theologian, and ‘Ālim who led the Iranian cultural renaissance in the 17th century. According to Oliver Leaman, Mulla Sadra is arguably the single most important and influential philosopher in the Muslim world in the last four hundred years.