Hello,
Pardon me if I’ve resurrected this old thread, but I’d just like to give my own opinion on what I find to be the most convincing argument for God’s existence. It’s funny because between the ontological and cosmological arguments, I used to find the latter more convincing. But after having read stuff from St. Augustine, Meister Eckhart and Descartes, I gradually changed my view. I once thought that the CA was more “grounded” since it took empirical reality as its data, unlike the OA which all seemed to be in the subjective mind. But then I realized that the CA also runs against its own problems like whether causality really exists, the contentious issue of fine tuning/design etc. If causality is denied then the CA (or some versions of it) could become ineffective. And there are indeed belief systems that deny causality such as Buddhism. Fine tuning/design on the other hand…well because I’m not a scientist, I feel that the complications of the issue is just beyond my competence
So about the OA, well I’m not actually sure if what I’ll type here is strictly an OA like that of St. Anselm. It’s more like an epistemological argument, haha. Actually I don’t know what it’s called! But I think Christian philosophers have been pointing this out since Augustine, and I’m certain they have a name for it. It’s about the paradox of human knowledge. How is it that we know the fact that there are things that we don’t know? Heck, why do we even care? Because, strictly speaking, if things that we don’t know are really things that we don’t know then we shouldn’t even know (and care) that we don’t know them. To phrase it differently: We know that we don’t know everything. However, by admitting that, we are also saying that there is precisely this “everything” that can be known, but as of now we only partly know. But the question then arises: How did we become aware of this “everything” and how could our minds even begin to comprehend it? Because the only way that we could be aware of it and comprehend it, is if we already knew everything. And also this “everything” isn’t something we can brush off as an idea we make up. Again, it’s an awareness -it’s simply a “given” without which our minds won’t even work properly. So it seems that the only reasonable answer is that this awareness of totality/everything is something which is "given’ to us by that which already knows everything.
This is actually similar to Descarte’s argument for God’s existence. Decartes said that perfection is an idea in his mind, and yet how could he have had this if he himself, and everything else, wasn’t perfect? Although his language makes it seem that the idea of perfection is more of a concept that he actively imagines, than an awareness.
Anyway, that’s all I have to say. I appreciate any feedback you all have since my knowledge of this is still sketchy at best

God bless!