Ottoman scholar İsmail Gelenbevî, who is mostly known for his works in the fields of mathematics and logic, was born in Gelenbe town of Kırkağaç district of Manisa in 1730. Ismail, who is famous with the nickname Gelenbevi in relation to his birth place, belongs to a well-known and cultured family. It is known that Gelenbevi’s grandfather Mahmud Efendi and his father Mustafa Efendi both worked as mudarris and mufti around Manisa. Gelenbevi started his primary education in Gelenbe, but lost his father at a young age, so he could not receive a serious education until the age of 13-14. After a while, he went to Istanbul to increase his knowledge and entered the Fatih Madrasa. He took courses in Arabic and religious sciences from Yasincizade Osman, one of the great scholars of the time, and logic, physics and mathematics from Muhammed Emin Efendi, known as the ‘Library with Foot’. After completing his madrasa education, he received the title of professor in 1763 and then attended lectures and negotiations at the house of Muhammed Emin Efendi.
It is stated that Gelenbevî was stuck between the fame of the two great scholars of that period while he was alive. According to the statement of Salih Zeki Bey, who is also an important scientist, his teacher Mehmet Emin Efendi suppressed the reputation of Gelenbevi in the sciences of philosophy, and Mehmet Efendi from Muğla suppressed his reputation in the science of mathematics. On the other hand, Gelenbevi left behind both scholars after his death with the works he left behind.
• Gelenbevi Ismail Efendi, who has a say in almost all branches of science; He is one of the important scientists who transferred the 18th century Ottoman understanding of science with his works.
• He wrote over 35 works on mathematics, astronomy, logic, philosophy, theology and mysticism.
• Gelenbevi is the first great master of logarithm in Turkey.
The treatise he wrote on this subject enlightened the path of mathematicians after him. Although he lived in a period when the Ottoman Empire started to decline with all its institutions, he was a versatile scientist who was able to transfer theory to the practical field, made his scientific competence accepted by the West and carried his fame beyond the borders of the state. Gelenbevi is the last mathematician to solve mathematical problems in the old fashioned way. It is clearly seen in the sources describing his period that Gelenbevî had superior talent in mathematics.