Priority of the Proof of the Truthfuls over all others for the Existence of Allah

Knowing existence in the system of  being  comprises one of the most significant issues of philosophy and mysticism. In the system of being s, existence in mysticism is regarded as one. That is to say, existence is exclusive to Allah Almighty and all else than Him is no more than His modes and states. It has gone celebrated that the first scholar who proposed the particular unity theory in a scientific system is Ibn Arabi followed by al-Qonawi, al-Qeisari, Turkah, Ibn Turkah, al-Fanari, and Mulla Sadra who tried to explain it philosophically. The author, however, holds that Suhravardi (Sheikh Ishraq) is the first person who before others come to deal with the issue. Nonetheless, since his theory that existence is mentally-posited (i'tibariyyate wujud) was construed as primacy of quiddity (Asalate Mahiyyat), his lofty ideas went veiled and unknown by the so-called primacy of quiddity. In what follows, the author has tried to prove that Sheikh Ishraq is the first one who has dealt with the personal  unity of existence.