P1. We observe that there are contingent beings (things that can possibly not exist).
P2. If it is possible for something to not exist, then there is some time in which it doesn’t exist.
C1. If everything were contingent, then at one time nothing existed.
P3. If nothing once existed, nothing could begin to exist, so nothing would exist now.
C2. So, there must be something that is not contingent, “having of itself its own necessity … That thing we call God.”
INfinite regress is implied from p2 to c1, however this is absurd, as nothing comes from nothing, so there must be something