Youth), and encounters angels who give him a "wonder-stone" that both weighs more than any other stone but is also as light as dust. This wonder-stone is meant to admonish Alexander for his ambitions and indicate that his lust for conquest and eternal life will not end until his death. The story of the wonder-stone is not found in the Syriac Christian legend, but is found in Jewish Talmudic traditions about Alexander as well as in Persian traditions. A South Arabian Alexander legend was written by the Yemenite traditionist Wahb ibn Munabbih (?–732 AD) and this legend was later incorporated in a book by Ibn Hisham (?–833 AD) regarding the history of the Himyarite Kingdom in ancient Yemen. In the Yemenite variation, Dhul-Qarnayn is identified with an ancient king of Yemen named Tubba', rather than Alexander the Great, but the Arabic story still describes the story of Alexander's Wall against Gog and Magog and his quest for the Water of Life. The story also mentions that Dhul-Qarnayn (Tubba') visited a castle with glass walls and visited the Brahmins of India. The South Arabian legend was composed within the context of the division between the South Arabs and North Arabs that began with the Battle of Marj Rahit in 684 AD and consolidated over two centuries. The Alexander romance also had an important influence on Arabic wisdom literature. In Secretum Secretorum ("Secret of Secrets", in Arabic Kitab sirr al-asrar), an encyclopedic Arabic treatise on a wide range of topics such as statecraft, ethics, physiognomy, alchemy, astrology, magic and medicine, Alexander appears as a speaker and subject of wise sayings and as a correspondent with figures such as Aristotle. The origins of the treatise are uncertain. No Greek original exists, though there are claims in the Arabic treatise that it was translated from the Greek into Syriac and from Syriac into Arabic by a well-known 9th century translator, Yahya ibn al-Bitriq (?–815 AD). It appears, however, that the treatise was actually composed originally in Arabic. In another example of Arabic wisdom literature relating to Alexander, Ibn al-Nadim (?–997 AD) refers to a work on divination titled The Drawing of Lots by Dhul-Qarnain and to a second work on divination by arrows titled The gift of Alexander, but only the titles of these works have survived. Notably, the Abbasid Caliph Al-Mu'tasim (794–842 AD) had ordered the translation of the Thesaurus Alexandri, a work