An investigation on the universal genus in the cotext of Aristoteles and Fârâbî

In this study, Aristotle who accepted founder of logic and Farabi who accepted in the Islamic world as the Second Teacher their aproaches to the subjects of genus and species evaluated under the roof of five predicables are tried to revealed. Our study consist an introduction, three chapters and a conclusion.In the introduction subject of thesis, purpose, method and sources were addressed. In the first chapter; the notions directly related to our study genus, species and substance were emphasised with their etymological origin, dictionary and terminological meanings. Some notions are analyzed related to this notions. In the second chapter; life of Aristotle, his works, his association with intension and extension, genus and species universals were emphasised with the context of Aristotle. In the third chapter, life of Farabi, his works, genus and species universals were emphasised with the context of Farabi. At the end of this chapter the data we derived are analyzed comparatively with the context of Aristotle, Porphyry and Farabi. Key Words: Aristotle, Farabi, Genus, Species, Substance