Аңдатпа
The paper presents an analysis of the scientific importance of the work “Diwani lugat it-turk”, or “Lugat”, by M. Kashgari, the author of the first scientific encyclopedia and father of Turkic languages’ comparative grammar. The scientific idea that studying M. Kashgari’s legacy is important not only for the history of the Turkic world, but also for the future prosperity and unity of Turkic nations. The article also thoroughly investigates M. Kashgari’s ideas and theories that pioneered in Turkic society throughout history. M. Kashgari’s opinions in “Lugat” about Kyrgyz, Kazakh, Oguz, Tokhsi, Yaghma, Chigil, Oghrak, Zharuq tribes speaking in only Turkic languages, the belonging of Iyamak and Bashkurt languages to Turkic, and the notion that ends of words in Bulgarian, Suar, and Bazhanak languages spoken in the land of Rum are a type of shortened Turkish are also given a scientific evaluation. The article reveals that the Medieval scientist’s ideas still hold true for the evolution of modern languages in the Turkic language family, such as the rarity of changes in words’ roots, and the cases of these changes happening usually presenting themselves as some sounds’ changing in pronunciation or being removed from usage. It is also identified that M. Kashgari’s analyses about the vastness of meaning in Turkic root words and the features of their individual changes are based upon the switching sounds.