Prove God exists
"it would be impossible for me to exist, being of such a nature as I am
(namely, having in me the idea of God), unless God did in fact exist."
Prove God cannot be a deceiver
"he cannot be a deceiver, for it is manifest by the light of nature that
all fraud and deception depend on some defect" (M3 52)
Prove that what he clearly perceives to be true is true.
"once I perceived that there is a God, and also understood . . . that
everything else depends on him, and that he is not a deceiver, I then
concluded that everything that I clearly and distinctly perceive is
necessarily true." (M5 70)
Prove that the mind is distinct from the body (P 225bf)
Prove that "corporeal things exist"
"But since God is not a deceiver, it is patently obvious that he does not
send me these ideas either immediately by himself, or even through the
mediation of some creature ... For since God has given me no faculty
whatsoever for making this determination, but instead has given me a
great inclination to believe that these ideas issue from corporeal things,
I fail to see how God could be understood not to be a deceiver, if these
ideas were to issue from a source other than corporeal things. And
consequently corporeal things exist." (M6 79f)