We say that a proposition p precludes a proposition q provided that p and q cannot both be true. We say that x is purely good provided that x is good and there is no defect in x.
- Necessarily, if x causes y, then it is impossible that y exists without x existing. (Follows from essentiality of origins.)
- Being essentially the cause of every pure good other than perhaps oneself is a perfection.
- If x is purely good and P is a perfection, then that something has P does not preclude that x exists and x is purely good and something has P.
- Something is purely good. (For instance, a photon.)
- There is something that is essentially the cause of every purely good thing other than perhaps itself.
We can run the argument without essentiality of origins with a tweak. Simply modify (3) to start "Being essentially the essential cause...", where the essential cause of something is a cause without which it cannot exist.