What is Descartes' perspective on the existence of objective reality?

Descartes believed in the existence of objective reality, which he argued could be known through reason and clear thinking. He famously stated, "Cogito, ergo sum" (I think, therefore I am), emphasizing the certainty of one's own existence as a thinking being. He believed that through rational inquiry, one could uncover truths about the external world and establish the existence of objective reality.