The philosopher, mathematician, and scientist René Descartes was an encyclopedic scholar and the founder of modern Western philosophy. His rationalist tradition sought to extend the paradigmatic mathematical methods of his era to the humanities or metaphysical domains (e.g., mind-body relationship, God, the world). As such, Descartes' philosophical system, represented by Meditations on First Philosophy, exhibits a high degree of systematicity and mathematical rigor. In this lecture, we will first present a reconstruction of Descartes' philosophical system (using approximately 60 propositions), analyze the basic axioms and fundamental concepts underpinning it, and then apply metaphilosophical criteria or models to reflect on and evaluate its validity. This will illuminate the system's metatheoretical nature and its worldview's common connections with mathematics and art.