Contemplation on the View Point of Sheikh Ishraq about Quiddity

In the history of Islamic thought, the question of the principality of the existence or quiddity has been propounded in transcendental philosophy for the first time, but what is famous is that the principality of the existence is cited to the Peripatetics and principality of the quiddity to Sheikh Ishraq. Now the question is that does Sheikh Ishraq believe in fiction of existence in the sense in transcendental philosophy? What reached after research is that Sheikh Ishraq does not believe in principality of the quiddity and fiction of the existence in the sense in transcendental philosophy. So, we cannot regard him as an essentialist. In this research, two reasons about the essentialism of Sheikh Ishraq have been criticized and some evidences have been provided for his existentialism.