Thank you Sair for your thoughtful reply and great points. Please allow me to respond drawing on my understanding of Aquinas.
This presupposes that the universe requires a reason to exist beyond simply existing.
As Aristotle points out, the very nature of the question “why” necessitates an answer. Maybe there is no specific or definitive answer; maybe, as Russell says, the universe is just there, a brute fact, requiring no further explanation at all. If that is the case, then that in itself is the answer to our question “Why”. But if this is the answer to the question then some case should be made to justify it instead of simply asserting it as though this answer were self-evident.
And even if further causes are required to explain the existence of the universe as we know it…then there is no reason to suppose this cause had any of the characteristics normally ascribed to the theistic concept of god.
I would agree with you that beyond necessity and immutability, cosmological and metaphysical/causal arguments for the existence of God do not provide us with a complete “description” of God as understood by classical theism. But the point of such arguments, as Aquinas explains, is not to assert the full range of doctrine about God, but to show that belief in God as a necessary, immutable being is not unjustified. That God is a Trinity, for example, requires faith and revelation; that a necessary being answering to the name “God” exists does not if the argument succeeds.
(since by itself, ‘universe’ as a technical term actually encompasses everything that exists)
In order to know this, you would have to know everything that exists to say that the universe is the sum totality of existing things. If, on the other hand, you are simply using the word ‘universe’ to mean everything that is actually (or potentially) existing, then this definition is simply another word for ‘everything’ and would therefore include God or gods, if indeed He/they exist.
In drawing a distinction between contingent and necessary beings, I have never seen an explanation as to why gods can be necessary beings whilst other contenders for the “ultimate” cause of the universe can’t.
Then may I suggest the following treatments of the question by Aquinas who does indeed offer an explanation to this very question: Summa Contra Gentiles Book 1 chapter 42.8; Summa Theologica, questions 14 and 19; Book 5 of the Commentary on Aristotle’s Metaphysics, in which he explains at length the nature of and relationship between necessary and contingent being and is quite a thoroughgoing answer to your question.
Also, might I suggest that there is perhaps a confusion here over the way in which the name “God” is being used. “God” is not being applied as an a priori premise, but is rather the name to the posterior conclusion. In other words, we are not starting with the assumption that God exists, then restricting all necessary possible causes to that definition. Rather, the argument asserts that there must be a necessary cause of the universe. The name we give to this necessary cause is God, after the fact. So any of your contenders which fit the bill will have this name, since the name God is equivalent to “the necessary cause of the universe”. You may then want to argue that there could be all kinds of causes that are not compatible with the Judeo-Christian concept of God, but I am quite confident that you will find an answer to these objections in the above passages.
If you would like to exchange further thoughts about this, I am very happy to do so. Please feel free to send me a message too, if you would like me to send you articles and or further citations.
Best wishes Sair…
Steve