First cause arguments of a Goedelian sort

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.

1. Necessarily, if x causes y, then it is impossible that y exists without x existing. (Follows from essentiality of origins.)
2. S5.
3. Being essentially the cause of every pure good other than perhaps oneself is a perfection.
4. 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.
5. Something is purely good. (For instance, a photon.)

Let x be the purely good thing. By (3) and (4), possibly x exists and x is purely good and something is essentially the cause of everything other than itself that is purely good. Call that something y. Then in some world w, y is the cause of x. By (1) and S5, y is actually the cause of x. By S5, y is also actually essentially the cause of every purely good thing other than itself. So:

6. 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.