This study aims to investigate the possibility of acquired knowledge of the reality of existence by employing a descriptive-analytical method and comprehensively examining various epistemological aspects of the concept of existence in Mullā Ṣadrā’s views. It seeks to answer whether the reality of existence is knowable, through which concepts it is knowable, and how these concepts are derived. With the help of Aqa Ali Modarres Zonoozi’s interpretation and by presenting a new argument as a complement to Mullā Ṣadrā’s reasoning, this research employs the tools and insights offered by Sadrian philosophy to negate conceptualization of the reality of existence. It will be demonstrated that although the essence of the reality of existence cannot be grasped through acquired knowledge, an acquired understanding can be achieved by contrasting it with non-existence. The concept of existence is derived from our perception of the negation of the other (i.e., non-existence) by the reality of existence, which we recognize as abstraction and mind. Since analyzing the concept of existence and the mechanism of its perception can provide a precise understanding of other philosophical concepts, we find that, in philosophy generally, the reality of existence is comprehended through abstract and mental concepts.