The concept of theory of Epicurus and its critics

The thesis aims to examine how the concept (prolepsis) theory, which was created Epicurus, a well know philosopher of the Hellenistic period, with his atomic approach to existence, was constructed. In this context Epicurus views on concept theory were examined, and the difference between Plato's understanding of given concepts and Aristotle's abstractionist approach to the concepts was stated. In the introduction, the purpose of the research, subject, scope, originality, and method of the research were evaluated and primary sources regarding the concept study were pointed out. In the first part of the thesis, the answer to the questions of "what is concept?" was sought and the function, of prolepsis in Epicurus epistemology was stated. Then simple compound and subtle-naive substances that form the basis of the philosopher's ontology were included. In the second part of the thesis, the position of sensation and image in Epicurus was mentioned, and the methods of conceptualizing what is directly subject to sensation, creating concepts by the inference method and creating concepts according to the purity of human nature are discussed. In the third and last part of the thesis, Stoics' and Sextus Empiricus' criticism of Epicurus over the concept of god, criticism of Sextus Empiricus and modern criticism about Epicurus understanding of concept were mentioned on the basis of Epicurus concept of God. As a consequence, it was concluded that Epicurus brought out a different viewpoint from Plato and Aristotle regarding the concept theory and therefore provided a new perspective with the aforementioned theory.