has been observed that Islamic philosophy had followed a bilateral development based on the ancient Greek philosophy and the religious mysticism and it was related with the Turkish opinions and understanding in both sides. There had been famous mystics that were trained among the disputes related with the Scriptures of Koran in the Islam world before the period of Turks. However, these mystics were local and individual persons. Actually, the religious mysticism was centralised around some specific unpolitic ideas and organised within the independent religious orders in the period of Turkish-Islam domination that was mostly considered as an era of religious and intellectual tolerance. On the other hand, the Greek philosophy had started to have an influence over the Islamic way of thought through the concentrated activities of translation in the period of the Caliph El-Me’mun (813-833). However, it was grateful to the Turks for its complete success. Actually, the Greek philosophy that was characterised with the qualities of material, scale, logic, and pragmatism was much closer to the Turkish way of thinking that was realistic in character rather than the Islamic thoughts that resulted from the “Sami” understanding based on the prohecy and the miracles. Therefore, the first real representative of the Greek philosophy was Farabi (died in 950) in the world of Islamic thoughts. Uzlug’s son, Muhammed Farabi that resided in the city of Karacuk (Fârâb) of Oguz people on the banks of Seyhun River had written nearly 160 books and dissertations in the fields of metaphysics, physics, astronomy, logic, psychology, policy, etc. Through these works, he had explained all of the opinions of Aristotles with the best explications. Therefore, he was known with the nickname of “Muallim-sânî" (the famous teacher) and he had acquired great fame with the name of “Al-Pharabius”. Most of his works had been translated into Latin language even in those periods and they had been taught within the curriculums of high schools as a textbook.

The era that Farabi had opened in the field of the reconciliation of the philosophy and the religion (reason and faith) was followed by Ibn Sina in the east and the Christian theologist Thomas Aquinas (ölm. 1274) in the West. Farabi who had studied upon the issue of policy had explained the “freedom” in such an interesting manner as follows: “Any person that can think right and that have the will to do what he/she thinks is free. The persons who cannot think right and who are deprived of their will are brutish (animals). If he/she can think right but is deprived of will, he/she is a slave. Some of the people related with science and philosophy do not lag behind the other people in slavery. No practical consequence can be achieved from their knowledge an also, they will be a source of shame for the other scientists and experts.”

The other great philosopher and physician was Ibn Sina (died in 1037) who had been trained within the cultural environment of Transoxania. He had followed the principles of Farabi related with the philosophical knowledge and this situation indicated the loftiness of the Islamic-Turkish culture. Ibn Sina (Avicennia in the West) had provided innovations in the scientific and intellectual world with his nearly 220 works written in the fields of medicine, logic, physics, natural sciences, moral values, religious philosophy, etc. He had been much influential in the East and the West as the 2nd greatest philosophers of Islam. Most of his works were translated into Latin language and they had been taught in educational institutions as a textbook.

There were also some people who followed the path opened by Farabi and developed by Ibn Sina and there were also some scholars who tried to reinforce this pursuit. The great characters such as Fahr’üd-dîn Râzî, Muhy’id-dîn Arabî, Ibn Rüşd and Gazâlî etc. had showed progress in the same “school”. However, these characters were not able to develop and diffuse this new philosophy. Furthermore, Gazzâlî and Muhy-id-dîn Arabî had played significant role in the diversion of this positive philosophy to another field. Therefore, the realistic philosophy was slowed down and it was forced to leave its place to the religious mysticism gradually. Especially Gazzali was the thinker that gave the best struggle against the positive philosophy. His famous work titled as Tehâfüt’ül-felâsife (Collapse of Philosophers) was criticised by Râzî and he had been severely opposed and rejected with the writings titled as Tehâfüt’ül-Tehâfüt) written by Ibn Rüşd (died in 1198). However, the influence of the mysticism stipulated by Gazzali could not be decreased in the east that was shaken with the political and social turmoil and conflicts. The thoughts of Gazzali could not be prevented to enter within the framework of the religion. Furthermore, various Shiite orders that were adopted by groups of people led to the total collapse of the high level of the religious philosophy.

As a consequence, the religious mysticism had gone beyond a religious-intellectual step and it became the stage of the unreasonable applications such as the forecast of the future, revealing the “veil of secrecy” and soothsaying, etc. From that date on, it was expected that each Sheikh or dervish would have a God-given power of working miracles. This situation deprived the communities from the mental power of positive thinking and it degenerated the widely accepted religious manners. At the same time, the crowded groups of people were estranged from the scientific thoughts and the realities. Furthermore, the ongoing struggles between the Muslim theological schools that gradually stereotyped the religious information and the dervish convents (the society of the religious orders) had nearly used up the mental thought and the world of science pertaining to the previous periods.

Therefore, it is required to examine the issue of positive sciences in two periods in the Islamic-Turkish states. In the first period that lasted until the middle of the 12th century, the sciences that had a power to guide the entire world like in the field of philosophy was nearly wiped off in the following periods.

The positive science had started with Farabi in the Turkish-Islamic communities. Farabi had classified the sciences in his book titled as Ihsâ’ül-ulûm. The translated version of this book in Latin language laid the foundation with its principles to the work of Gundisallinus (died in 1157) upon the same issue. Farabi had also explained and annotated the Euclidean geometry. Among the other scientists, we should also mention about Abdullah al-Bârânî (died in 929) of Turkish origin that was comsidered as one of the founders of the trigonometry and Ibn Turk’ul-Cili, the author of the work titled as Kitab’ül-Cebr ve’l-Mukabele that was one of the principal representatives of the science of mathematics in the east. One of the scholars of mathematics was Abu Reyhan’ül-Bîrûnî (died in 1051) from Harezm.

El Biruni who was probably of Turkish origin had lived in the Turkish palace of Gazne and participated in the military expeditions of Sultan Mahmud to India. In his works, he had cited the “Verses of the Koran” together with the sayings of the philosophers and this quality was of great significance. According to him, the freethinking was a must for the development of science and he stated that “People had various different ideas and faiths. The developments (civilisations) result from this variety of differences”. El-Biruni who had come into existence as a contemporary and modern scientist with his free thoughts had written more than 100 works in various fields of his knowledge. In his work titled as Istahraç’ül-Avtar fi’d-Dâire, he had supposed new theorems about the ringed springs and beams; and in his work titled as Tasdik’us-Suver, he had studied upon the procedures of geometric projections. His original thoughts upon the classical matter of geometry that cannot be resolved with only a pair of compasses and rulers is still called as “Biruni Problems”. His work titled as Tahdid Nihayet’il-Emâkin was a book about the examination of mathematical geography and some of trigonometric issues were explained within this book. El-Biruni was considered “as one of scientific and intellectual geniuses in the type of Archimedes, Leonardo and Leibniz of the world history”.

Farabi had explained the unfounded efforts in relation with soothsaying and fortune telling from the stars (ilm-i Nücum). According to Farabi, it as not possible to foretell the futures and destinies of people from the creatures and events that took place in the sky. The belief in the relation between an event in the sky such as the solar eclipse that took place when the moon interrupts light from the sun to the earth and a death of a ruler on the earth is “acab al-acaib”(the trumpery of trumperies). According to Farabi, there is a reason for each event: “The chance events are the incidents with the reasons that we do not know”. Ibn Sina had worked in the observatory in Hemedan and el-Biruni had mentioned about the event that the world orbited around the sun in a year within his work titled as Tarih’ül-Hint. In his other work titled as El-Kanun’ul-Mes’ûdî (written in the name of Gazneli Sultan Mes’ûd I), he had dealt with the parallels and meridians and he had determined the dimensions of the earth and the parallel and meridian circles between Gazne-Alexandria. Ibn Sina had stated that he did not believe in the “Philosopher Stone” that was alleged to turn each metal that it touches to the gold and the “elixir” that was believed to maintain life indefinitely and he stated that all these things were the visions of imagination. Pursuant to Ibn Sina, el-Biruni had reached to important results in relation with the issue of specific gravity in his work titled as El-Cemahir Fi Ma’rifet’il-Cevahir for the first time in history. He had also invented a pycnometre and measured the specific gravity of 16 materials with the values much closer to the real values.

It is beyond doubt that Ibn Sina is in the first line in respect of medicine in Islamic-Turkish world. He was called as “ruler of medicine” in the Western world of sciences. The work of Biruni titled as Kitab’üs-Saydele was written about the medicines and the curative herbs.

While the geography was composed of only the knowledge of observations in the Islam world in the past, it was turned into a branch of science in the period of Turkish-Islam era. In his work titled as Tahkik ma li’l-Hint, el Biruni had dealt with the history, geography, traditions and customs of India where he had visited together with Sultan Mahmud and he had given detailed and comprehensive information about the geography of this continent. Furthermore, he had stated that the valley of Indus was the residue of an ancient sea that was filled in with the deposit of alluvion. In his work titled as Tahdid’ül-Emâkin, he had recorded his geological determinations about India, Afghanistan and Harezm.

The work titled as Es-Sihah fîl-luga or Sihah-i Cevheri was considered as one of the best dictionaries in the Arabian language in respect of philology. Ismail Cevheri (died in 1002) who was the author of this work was a Turk from Farab as stated within the resources. Several history books were written in this period. However, most of these books have not survived until nowadays.

The work titled as Kutadgu-Bilig that was written in Turkish and in verse in the country of the Kara-Hanli State was doubtlessly a masterpiece in respect of Turkish state thoughts, the understanding of laws, the views about domination and the political opinions. This book was written by Balasagunlu Has Hâcib Yusuf in Kasgar with the Uighur letters towards the year of 1070 and it was presented to Bugra Khan (Ebu Ali Hasan). Another book that was written in Turkish and in verse genre with the Uighur alphabet was the work titled as Atabet’ul-Hakayik that was written by a Turk named as Yüknek’ Ahmed in the name of Emîr-i Dâd (Minister of Justice) Muhammed Bey. In respect of time, this work was written after a little period pursuant to Kutadgu Bilig and it was mostly in the quality of a book of advice. It has been observed that the influence of the religion of Islam was much more effective in this book. There was also a book of policy-ethics titled as Agrâz’üs-Siyase fî İlm-il-Riyase that was written in the name of Mes’ud II (died in 1178) who was one of the rulers of the Western Kara-Hanli State.

It has been known that the period of Seljuk Empire was a turning point in respect of training and education in the world of Islam. The education that had been provided in a disorganised and private manner in the past was programmed in the period of Sultan Alp Arslan for the first time in history and the educational issues were taken under the protection of the states. One of the main reasons that led the Seljuk State to orientate towards these serious cultural activities was the struggle against the Shiah Islam and the other Rafizi (Shiite) opinions as required by the main policy. In the beginning, the front of spiritual forces faithful to the state was established through the allocation of allowances for the Muslim jurists and the scholars and the foundations of charitable establishments for the devotees. In the further periods, the Muslim theological schools were established as the big societies of sciences and the educational order was organised with personnel all over the empire. Therefore, the Muslim theological schools accommodated the famous scholars and intellectual men within their structures and they had instructors (professors) that were paid salaries. Furthermore, it provided gratuitous education for the students that were also granted with salaries and provisions. The curriculum programs were determined for these theological schools and they were donated with rich libraries. The first Muslim theological school that was in the level of the highest educational institution was founded by Sultan Alp Arslan in the world of Islam (1066).

According to the rumours, this Muslim theological school that was called as “Nizamiye” was founded with an expenditure of 60 thousands of dinars (gold) in Baghdad and bazaars, inns, public baths and farms were dedicated to this theological school. Baghdad Nizamiye that taught the Hanafi and Shafi faiths of the canon jurisprudence in respect of religion had played an important role in the world of science and opinions. These Muslim theological schools had trained high-qualified scholars and the young people who graduated from these schools had been promoted to the high-rank offices as the authorised characters of the country. Similarly, in the same period, Similar Muslim theological schools were constructed in some centres such as Isfahan, Nişâpur, Merv, Belh, Herat, Tûs, Basra, and Âmul, etc. The course subjects and curriculums of Baghdad Nizamiye were followed and applied in principle in all of the Islam countries and in all the Islamic-Turkish states including the Ottoman Empire for centuries.

The sciences such as philosophy (Scriptures of Koran), philology (Arabian language and grammar) and mathematics (riyaziyat= mathematics, hey’et= astronomy), etc. were also taught inn Nizamiye Muslim theological schools as well as the religious information. Since the similar institutions were established in the later periods in Europe, Baghdad Nizamiye was considered as the first university in the world. Afterwards, there were numerous theological schools founded on the same principles by the rulers, statesmen and hatun (ruler’s wive) people in the Seljuk States, Harezmshah State, the Tutor Principalities, Turkmen principalities, India and Egypt. Furthermore, the Muslim theological schools were of great importance since they trained civil officials for the administration of the state.

In the period of Seljuk State, doctors and orators were trained and the science of mathematics had reached to a highly developed level. Famous Ömer Hayyâm (died in 1131) who was mostly known with his literary identity had found some powerful representatives such as Muhammed Beyhâkî. Furthermore, an observatory was founded between the years of 1074-1075 and some studies were carried out in this observatory. The greatest astronomers such as Ömer Hayyâm, Ebu’l-Muzaffer İsfizarî, İbn Necûb’ül-Vâsıtî, etc. had arranged a calendar that was called as “Târih-i Melîkî” or “Târih-i Celâlî” or “Takvim-i Melikşahî”. This calendar was based on much more accurate estimations than the Gregorian calendar that is used today.

Like all of the Turkish rulers, the Seljuk Sultans had encouraged for the development of the historical knowledge. Therefore, the works that are dealt to be originated in the period of Seljuk State are the outputs of this era.

There was a work titled as Danishmendname famous with its epics that dealt with the life and wars of Dânişmend Ghazi Ahmed Bey.

Furthermore, there were some books written with the Oguz dialect in the country of Egypt.