Epistemological Critique of the Simplicity and Otherness in the Existence

The existence is a categorical concept according to Kant’s philosophy. Kant, going to be a subjectivist philosopher, negates the existence as a perfection and concludes the separation between the mind and extra-mental world. But the externality is not an origin which we deny it easily, even if it is faced with multiple problems such as the issue of simplicity and multiplicity and also being historical and non-historical. The issue is that how we can go out of these dilemmas.
According to the rule of extraneousness (Qaidah al-Far’iyyah) as a basic rule in Islamic Philosophy, we can criticize Anti-Realism as we provide some proofs about the existence which is common between the mind and the extra-mental world. the existence which connects the mind to the extra-mental world. The reality of the existence is simple and it includes all multiplicities in its absoluteness; therefore, it would be for all existents according to its essence.
Therefore, on the base of the gradation of the existence, existence’s multiplicity is originated in the limits of its simplicity. What is existed is faced with the existence in its singularity. The existence is a simple reality which is presented in the “Others” while its simplicity has been meant as being absence. So the multiplicity and otherness is the limitation of the existence.