In post #7 I wrote:
2. The class of more traditional cosmological arguments, derived from Aristotle by way of Aquinas. ...
This class of arguments seems to me to revolve around a whole class of unanswered metaphysical questions, (How did reality originate? What is the source of its order?) It doesn't really point to a theistic-style deity unless one introduces the deity as an additional premise which would semingly render the arguments circular.
The argument that starts with "Everything must have a cause" and then goes on to create an ad hoc exemption for God is fatally flawed, in my opinion.
I'm inclined to agree that the cosmological arguments are flawed, but perhaps it's more subtle than that.
Certainly some of the more historic cosmological arguments (the 'first-cause' version) do seem to revolve around causality. The 'unmoved mover' might as well, though one has to get into Aristotle's head to understand what he meant by 'movement'.
But it's possible to concoct more subtle cosmological arguments that don't need to imagine first causes or the idea that infinite regresses are repellent. Imagine that time extends infinitely into the past and future. And imagine a chain of causes that extends infinitely into the past, with no origin of the chain and no first cause. Even then, when a first-cause or an unmoved mover has been ruled our
ex hypothesi, one could still ask why there is an infinite endless chain of causes rather than nothing at all. It's a different kind of question.
What's being sought isn't a
cause, so much as an
explanation. It raises the issue of what Leibniz called the Principle of Sufficient Reason. That's the idea that everything must have a reason, cause or ground. While it might be hard to justify that idea as a metaphysical principle (Spinoza tries to derive it from
ex nihilo, nihil fit, 'from nothing, nothing comes') it might arguably be introduced as a requirement for intelligibility. Science certainly seems to presuppose it (most of the time). Otherwise we would just be accepting our experience as given, as 'brute facts', and not even trying to understand it.
Applying the Principle of Sufficient Reason to reality as a whole, we seemingly are pointed towards... some unknown explanation... that transcends what we take to be reality as a whole. That's obviously problematic on its face and may be self-contradictory. (Since the scope of 'reality' might extend to anything we might cite to explain reality, rendering all possible answers circular.)
If we continue to seek an explanation, then this sort of thinking points us towards the need for an explanation whose nature may be incomprehensible to beings like us. We have no idea what form the explanation might take or what it might look like. It's basically a question that we have no idea how to answer at this point.
Personally speaking, I feel it rather strongly. The universe doesn't appear to my eyes as a closed system so much as a cosmic mystery. Something is obviously going on all around, and I don't begin to know what it is. I don't think that anyone knows. (Hence my agnosticism.)