The problem of universals and the relationship of quiddity in Ibn Sina

As a philosopher of existence, Avicenna influenced the philosophical, theological and mystical systems of all thinkers who would come after him, together with the theory of existence and essence. In this study, by proving the identity of the absolute essence with the natural universal, the effect of this identity on the solutions of the universals problem, which was considered a major problem in the Middle Ages, was tried to be revealed. The study is based on the reputations of essence and universal classifications in Avicenna. In addition, it is argued that in the relation between the universal and the quiddity, the rational universal can be mentioned in the mental universal in the identity of quiddity in the outside world, since the mental universal is identical with the quiddity in the mind in terms of the universality accident. As a result, mental existence means that the absolute quiddity, which is the quiddity in the external world, is identical to the quiddity, that is, the abstract quiddity, in the mind.