Mu?min Husayn Yazdi (d. 1018/1609) was an Islamic scholar and a poet. Born in Yazd around 948/1541, his father was librarian to the governor of Yazd at the time, Shah Ni?matallah Baqi (d. 994/1586 or 996/1588). Ever since his childhood, Mu?min was eager to learn. Thanks to his father he could go to Shiraz in search of higher education. There he followed the lectures of, among others, Mulla Baghnawi (d. 995/1587), the famous academic and author of a whole series of glosses and super-commentaries on works in philosophy, theology, and logic. Mu?min became a respected scholar and even resided in Mekka for a time, besides visiting the holy cities of Najaf, Karbala, and Mashhad. As a specialist of quatrains Mu?min can be compared to authors like ?Umar Khayyam (d. ca 517/1123) or Baba Afdal Kashani (d.667/1268-69). In the latter part of his life Mu?min went through a mental crisis, choosing a life of isolation.