Mathematician and physician (B. 1864, Istanbul – D. July 14th, 1921, Istanbul) He was born to a poor family. He was the son of Hasan Aga and Saniye Hanım from Boyat, Kastamonu. He was the first husband of Halide Edip Adıvar when he married her in 1901. He was the student of Fatih Hoca (Gökmen), the founder of the Kandilli Observatory. He was grown up by his grandmother when his father left them upon the death of his mother. Her grandmother sent him to a Mahalle Mektebi (local primary school) but he was taken from there upon the request of his teacher due to his mischievousness and was sent to a craftsman for apprentice training.
He was sent to Darüşşafaka High School, the school of orphans, at the age of ten in 1874 and he graduated at the top of his class from there in 1882. He attracted his teachers’ attention with his intelligence and his talent in mathematics thus being trained with a special attention by his mathematics, physics and chemistry teacher Mehmet Nadir Bey. He was sent to Paris to be trained as an expert telegraph engineer and physician by the Ministry of Post and Telegraph in 1882. He was nicknamed “intelligent” (Zeki) by his friends for he succeeded in the solution of an integral problem when he was a student at Higher School of Engineering thus he was called Salih Zeki.
He wanted to stay there and to do a post graduate study but he was called back by the Ministry of Post and Telegraph and returned to the homeland. When he completed his education at the Higher School of Polytechnic in France, he returned to Istanbul and began to work as electrical engineer and telegraph auditor in 1887 and there he met Monsieur Lemoine, the Director of Credit Lyonnais. With the encouragement of Monsieur Lemoine, he began to show interest in mathematics and the history of astronomy. He wanted to enlighten the scientific works of Medieval Islamic World. He first submitted himself on antique Greek and Indian works and then examined old compositions. In 1889, he published his first article on the history of science “Hint Rakamları Üzerine Bir Rapor.” After that, he was additionally appointed to Mekteb-i Mülkiye-i Şâhâne (School of Political Science) as the professor of hikmet-i tabiiye (physics) and chemistry. In 1895 he was appointed to the Observatory Presidency and after the Proclamation of Constitutionalism, he was appointed as a member of education committee, Maarif Nezareti Meclis-i Maarif (Education Committee of the Ministry of National Education) (1908).
He was appointed as the principal of Galatasary Sultanisi (High School) upon the resignation of Tevfik Fikret in 1910. He became the Rector of Darülfünun (Istanbul University) in 1913. After that, he devoted himself only to the lessons at the Department of Riyaziye (Mathematic), at the Faculty of Fünun (Science). In the first years of his career in teaching profession, he taught mathematics and physics lessons at Darüşşafaka, Navy Academy, Mülkiye Mektebi and Higher School of Engineering. In the meantime, he taught French and science lessons voluntarily at Darüşşafaka where he graduated from. He composed monographs, in which he described unknown authors and works and he published them in Resmi Gazate in 1892. Thanks to that work, he had the background information for his Asar-ı Bakiye (Immortal Works) which was an important work of him. He wrote the book Hikmet-i Tabbiye (Phycisc) co-operated with his friend Ahmet Fahri.
That book written for high school education was published in 1892. Salih Zeki Bey, who became the director of Beyoğlu Observatory in 1895, gave private lessons to Halide Edip (Adıvar) who was a senior student in Üsküdar Amerikan High School in 1900. Salih Zeki Bey had married for three times and one of them was to the writer Halide Edip Adıvar. Piano virtuous Vecihe Nanım was his first wife and they had a son, the Geology Engineer Malik Sayar, from that marriage. His second marriage was to Halide Edip Adıvar and they had two sons, Ayetullah (who had been deputy for a while, D. 1985) and Hasan Hikmetullah Togo from that marriage. Salih Zeki Bey married his third wife Münevver Hanım, a teacher, (D. 1973) when he was the principal of Galatasary High School. They had two sons, Tarık and Faruk (Sayar). Salih Zeki Bey, who became Maarif Nezareti Müsteşarlığı (T.N. undersecretary of Ministry of Education) in 1912, published the first and second volumes of his book “Darülfünun Konferansları.” In his lectures, he introduced “Non-euclidian geometry” and “various squares based on nominal proportion” which was unknown to Turkish mathematicians. In the same year, he translated French mathematician and philosopher Jules-Henri Poincare’s works on philosophy of science into Turkish. In 1913 he became the rector of Darülfünün-ı Osmanî (Istanbul University).
He resigned from the rector duty in 1917 but kept his office there as the professor at the Faculty of Science. In 1919 he became the dean of the Faculty of Science. He brought German lecturers when he was the rector of the University, but those lecturers had to return to Germany due to World War I. Unfortunately, Salih Zeki Bey got a mental illness in 1920 and lived insane until his death. He was given medical treatment at French Hospital, Şişli, Istanbul but he couldn’t recover from that illness and passed away.
He was buried in the yard of Fatih Mosque. Sali Zeki Bey’s most important works are two-volume book Asâr-ı Bakiye on Medieval mathematics, encyclopedia Kamûs-ı Riyaziyat on mathematics and physics and Mizân-ı Tefekkür, which he wrote with the translations of philosophy of science and morals. While he was a lecturer at Darülfünûn, he gave many lectures, wrote critical articles on positive sciences in daily newspapers and some magazines. He published articles and surveys in the newspaper İkdam, magazines İktisadiyat and Darülfünûn. He got into arguments with noted journalist-writer Ahmet Mithat Efendi on theories of music, with İzmirli Ferit Efendi on science, with mathematician Mehmet Emin Bey on order of an algebra equation and even on diving an angle into three pieces (teslis-i zavâyâ).
He got into arguments with Ali Sedat Bey (1856-900), who was a noted logician, on old and new issues about logic. It is accepted that in Salih Zeki Bey’s article there was a clear, powerful and strong-patterned connection. In sources he was regarded as “a scientist with a genius and intelligence and talent of mathematics” and regarded as “the founder of the history of science in Turkey”. He was one of the noted Ottoman mathematicians during the last times of the empire. He tried to analyze the contributions of Turks and Muslims in science from an objective point and became the founder of the history of modern science in Turkey. His book Asar-ı Bakiye is still a reliable source today.
He did studies on the philosophy of science and introduced it to Turkey with his translations from Henri Poincaré and Alexis Bertrand. He got into arguments with famous scholars of the era on mathematics and science and composed many works, some of which was course books and some of which were translation on those issues. His four books translated from Henri Poincaré are among his non-published compositions. Salih Zeki Bey has many works on mathematics, physics and astronomy such as Hikmet-i Tabiye, Elektrik-i Mıknatısi, Cazibe-i Umumiye, Hisab-ı İhtimali, Nazariye-yi Temevvücat.
Âsâr-ı Bâkiye (Immortal Works. History of Medieval Mathematic, 2 volumes, 1913), Dârülfünun Konferansları (1915), Mîzân-ı Tefekkür (a book on logic, 1916), Kamûs-ı Riyâziyât (encyclopedia of mathematic and astronomy and physics, an unfinished composition, 1924), Hendese (Geometry), Hikmet-i Tabiiye (Physics), Mebhas-ı Savt (phonologia), Mebhas-ı Elektrik-i Miknatisi (electro magnetism); Mebhas-ı Hararet-i Harekiye (thermodynamics), Mebhas-ı Cazibeyi Umumiye (universal gravitation), Mebhas-ı Elektrikiyet ve Şariyet (Electrics and capillarity), Hesab-ı İhtimali (calculation of probabilities), Mebhas-ı Hareket-i Seyalat (fluid motion), Hendese-i Tahliliye (Analytic geometry), Mebhas-ı Nazariye-i Temevvücat (wave theory), Heyet-i Riyaziye (Mathematic Astronomy).
TRANSLATIONS: İlim ve Faraziye - Felsefe-i İlmiye (from Henri Poincaré, 1906), İlmin Kıymeti (from Poincare, 1914), Kamus-u Riyaziyat I (Mathematic encyclopedia); Asar-ı Bakiye (Immortal Works).
REFERENCE: İbrahim Alaeddin Gövsa / “Salih Zeki” (Türk Meşhurları, 1946), Mücellidoğlu Ali Çankaya / Yeni Mülkiye Tarihi ve Mülkiyeliler (c. 2, 1968), Salim Aydüz / “Salih Zeki” (Yaşamları ve Yapıtlarıyla Osmanlılar Ansiklopedisi, c. 2, 1999), Celal Saraç / Salih Zeki Bey: Hayatı ve Eserleri (Yay. Haz. Yeşim Işıl Ülman, 2001), İhsan Işık / Resimli ve Metin Örnekli Türkiye Edebiyatçılar ve Kültür Adamları Ansiklopedisi (2006, gen. 2. bas. 2007) – Ünlü Bilim Adamları (Türkiye Ünlüleri Ansiklopedisi, C. 2, 2013) - Encyclopedia of Turkey’s Famous People (2013).