Explore Rene Descartes' third Meditation on First Philosophy in this 44-minute video lecture, part of an introduction to philosophy course. Delve into Descartes' cosmological proof for God's existence, which begins with his concept of an all-perfect being. Examine the argument that only a creature with infinite formal reality could create an idea with infinite objective reality, leading to the conclusion that God must exist. Follow the lecture's structure, covering topics such as the veil of perception, ideas and objects, mental images, degrees of reality, and objective reality. Engage with a quiz and controversial applications of the concept. For a comprehensive understanding, consider watching the accompanying videos on the first and second meditations, as well as an explanation of the difference between arguments and conclusions.