1. Is God a Deceiver? (P1)The idea I have of God is of an infinitely perfect being. (P2)The cause of such an idea must itself be infinitely perfect. (P3)Therefore, god is infinitely perfect. (P4)Deception is a sign of imperfection. (P5)Being perfect, God cannot deceive. (C)Therefore, God is not a deceiver.

2. First Version of Descartes’ Ontological Argument (P1)Whatever I clearly and distinctly perceive to be contained in the idea of something is true of that thing. (P2)I clearly and distinctly perceive that necessary existence is contained in the idea of God. (C)Therefore, God exists. Second Version of Descartes’ Ontological Argument (P1)I have an idea of a supremely perfect being—a being having all perfections. (P2)Necessary existence is a perfection. (C)Therefore, a supremely perfect being exists.

3. Proof of the Independence of Mind and Body (P1)It is possible for God to create anything I can clearly and distinctly perceive. (P2)If God creates something to be independent of another, they are distinct from each other. (P3)I clearly and distinctly understand my existence as a thinking, non-extended thing. (P4)I clearly and distinctly understand my body as a non- thinking, extended thing. (C)So I am distinct from, and can exist without, a body.

4. Proof of the Existence of Physical Objects (P1)I have a passive ability to sense (to receive and recognize ideas of sensible things). (P2)I wouldn’t be able to use this ability if there weren’t some active power to produce sensory ideas. (P3)Since this active power is prior to my understanding, and does not operate according to my will, it cannot exist in me. (P4)So this active power must exist in some substance distinct from me (which must contain at least as much reality as there is presented in the ideas it produces). (P5)Then, either: (i) this substance is the physical objects themselves; or (ii) this substance is God. (P6)If this substance were God, I would know this, for God is not a deceiver, and I have a “strong inclination” to believe that the ideas come from physical objects. (C)So the substance is the physical objects themselves, and therefore, physical objects exist.