Aquinas never claimed that he proved the First Mover to be the God of Abraham.

Correct. I was mistaken.

that must have many of the same characteristics the Abrahamic God must have, oneness, omnipotence, pure goodness, transcendence, immateriality

At this he largely failed.

Revelation is beyond reason, but Aquinas's arguments establish that it does not contradict reason.

What happens if revelation contradicts reason? Do we revise our understanding of revelation or of our reason?

you're probably right that some of what we consider common sense, like reality exists and isn't just an illusion, could be considered metaphysics.

You are (possibly deliberately) missing the point. You believe that only what can be empirically verified should be accepted as true. Please describe a non-question-begging way to establish with your senses that your senses can verify anything. Hume established more than two centuries ago that causality cannot be perceived with the senses. Yet empirical verification (which presupposes a reality independent of our sensory perception) and its amplification by measurement with instrumentation and/or repeatable experimentation (which presuppose causality) is the heart of science. The point is that you dismiss metaphysics in the name of a science that is itself based in metaphysical principles it cannot by its own methods verify.

You yourself point to an article that you believe falsifies Aristotelian/Thomist metaphysics. I can't comment on it specifically because it's behind a pay wall. Of course, it's always possible to argue that a particular objection is mistaken about what the premises of a metaphysical argument are or whether they are true, and it is equally possible to argue that an objection is based on a misunderstanding of the reasoning of a metaphysical argument. Nonetheless, in principle what I said in my previous comment holds. The fact that scientists do not consider metaphysics to do what they do has zero bearing on my argument. I know next to nothing about the principles of the internal combustion engine, yet I drive every day. That does not in the least change the fact that I could not drive if the principles of the internal combustion engine were not operative. And since I cannot read the article to which you link without spending money I don't have for a subscription I'm not interested in, perhaps you could elaborate on how relativity "messes up my metaphysics."

Aquinas never claimed that he proved the First Mover to be the God of Abraham. What he did do was establish that human reason can lead us to a First Mover that must have many of the same characteristics the Abrahamic God must have, oneness, omnipotence, pure goodness, transcendence, immateriality, etc. He believed that revelation established that they were the same. Revelation is beyond reason, but Aquinas's arguments establish that it does not contradict reason. Truth is one. Hope that helps.

But there are ways to falsify metaphysical arguments. If they are based on premises that can be proven false or flaws in the logic can be pointed out, they are thereby falsified. And science, by virtue of what it does, presupposes certain things it cannot itself verify, e.g. that objects exist outside our sensory perception of them, that our senses perceive objects more or less accurately and when they don't they can be corrected by further perception or measurement with instrumentation, that cause and effect exist. Those are all metaphysical ideas, not scientific ones, yet science by its nature implies them.

Undisputed among who?

Among the parties to the debate. If you say that X is inconsistent with God's nonexistence, I may or may not agree that X is a fact, but if I do agree, then at least between you and me, X is undisputed, and whether anyone else disputes it doesn't concern us. And, if X is undisputed in that sense, then we can focus our debate on the particular issue of whether it is inconsistent with God's nonexistence.

If X is disputed, i.e. I don't believe it is a fact, then its theological implications are, at least me, epistemologically irrelevant. If X implies T, then I make no logical error if I deny T so long as I don't affirm X. Whether I ought to be affirming X is a separate issue, but it needs to be addressed before we can argue about T.

Undisputed among who? I mean you can say an undisputed fact but I find that even this definition becomes a moving target when pressed. So as long as we're looking for undisputed facts, what do you think that might look like?

An undisputed fact that is inconsistent with God's nonexistence.

There are plenty of documents for you to read on the matter, it's not about a matter of whether or not it exists, but rather if you'll accept it.

In short, we can at least determine what God is not and what he is within the boundaries of our concepts and terms. It's ultimately a practice in metaphysics.

From the onset one must first take into account what metaphysical framework corresponds to reality. I believe the Aristotelia-Thomistic view fit this criteria and has yet to be truly refuted (though that is not the reason why I believe it is true).

The 4 causes are a starting point for understanding everything and from there we can work our way up to the concept of God put forth, however "vague" it is to you, just like Aristotle did pre-Judeo-Christianity and without any exposure to it.

If we take some simple like a chair and ask what makes up that chair we can refer to 4 causes. The material, formal, efficient, final.

Wooden Chair:

Material: The material from which it is made, the thing that makes up the chair. The wood.

Formal: The form of the chair that makes up its "chairness", such as the seat connected to the legs and the support for the back.

Efficient: The moving cause that made the chair, such as the Carpenter or machine

Final: The purpose for which it exists, i.e. to sit.

This account of reality I hardly find objectionable and for the most part science deals with all the top three and often times eschews the the last. But nothing makes sense unless this final cause exists.

Taking that into account and without going into it comprehensively, we can look at something as basic as a chair and look at certain like the fact that is it sitting on the floor and begin to analyze what, in this moment, is causing the chair to be HERE AND NOW.

The chair standing on the floor, exists here and now, partly because it was first created and left to itself being dependent upon both the form it took (from the mover, the "efficient cause") and the material from which it was made (the wood). But it also exists here and now because it is dependent upon a heirarchy of immediate causes, such as the floor it stands on which is supported by the foundation of the house, which is supported by the earth directly under it, which is HERE AND NOW supported by the total sum of the earth and its position in our solar system and other things like gravity. S

So at any given moment those things (the floor, the earth, gravity) are not necessarily linear causes but hierarchical causes that sustain the chair existing where it does here and now. But in order for any of it to exist, both the form, the material, etc., there must be a sustaining efficient cause that sustains it HERE AND NOW.

This sustaining efficient cause for the chairs existence must itself be self-sustaining and in order for that to happen it would have be be existence itself, which exactly what Aquinas say: ipsum esse subsistens.

Can we know the totality of what that is? No, but can we infer that it must exist? Yes. How, based on all that we know about reality and the impossibility of anything existing HERE AND NOW without an imminent efficient cause.

I probably butchered this argument, but I'm also rushing it. This is far from a complete account of it and possible somewhat error prone if my language wasn't clear enough.