Abstract

One of the philosophical issues whose true place and significance have been neglected is the addition of existence to quiddity. An accurate study of this issue on the basis of the doctrine of the principilaity of existence and its external unity with quiddity requires a specific interpretation of Mulla Sadra's words.In this paper the writer has tried to provide a specific interpretation of Mulla Sadra's doctrine of the principiality of existence and the relation between quiddity and existence, correct the interpretation and explanation of the place of the issue of the addition of existence to quiddity, study the philosophical works related to this topic, interpret Ash'arites' words concerning the semantic unity of existence and quiddity, modify the view of the issue of "God's existence is the same as His quiddity", explain the theory of apparition in mental existence on the basis of the principiality of existence and quiddity, present a solution for it, and clarify the existence of natural universal in the outside. In doing so, the writer has tried to follow a number of innovative approaches.