Which Islamic sciences are concerned with the issue of proving existence, and which form the basis for discussing existence in its various forms, citing the statement "I think, therefore I am"?

These ideas were conceived by philosophers who are not illuminated by revelation, and they are based on delusions. Denying the existence of something perceptible by the senses is ignorance. Islamic scholars do not waste their time proving what has been affirmed by widespread consensus, just as they did not adopt the idea of "I think, therefore I am"; for they are far removed from such intellectual fallacies. As for proving the existence of Allah and the unseen, they gave it great attention and proved it with both textual and rational evidences.