OK. IN reading your post, a rather strained hypothetical popped into my head.
Suppose, and it’s a stretch, that the Pope convened a council, and after much deliberation, determined that the current “Church X” sect of Christianity was, in fact, the one most closely following what God intended. And so, they ruled so as to align Catholic teaching and doctrine with “Church X”.
In my mind, that would suggest that “Church X” was in fact the “true church”, and had claim to the bloodline, rather than the Catholic Church, who again by external observation would appear to have strayed off the tracks (which lead to the foundation of “CHurch X”) and has only now come back onto the tracks by rejoining the beliefs of Church X.
But by the previous arguments made by others, I would expect the Catholic Church to still claim the bloodline, and maybe even to insist that during the time the Catholic teaching was not in accord with “Church X”, that in fact “Church X” was wrong in it’s teaching, and therefore had no claim to the bloodline.
Now, it is easy to answer this hypothetical by a claim that the Church, being infallible in it’s keeping of the keys of the faith, could not possibly have gotten into such a mess as to require the affirmation of “Church X”.
But if you can postulate the possibility of such a schism, does it not suggest, as I assert, that from an outside observer’s point of view, the claim of the bloodline seems self-fulfilling, and by the definition set forth by Catholics here, has no outcome but to affirm by assertion that the Catholic Church is and always has been the “one true church”?
Because it seems that only by asserting that it is impossible for the Catholic church to ever stray from that path such that it no longer has the “keys” to the church, claimants are simply saying “the Catholic church is the true church because that is the definition of the true church”.
I argue this way because, only if both sides admit the possibility of an error in church doctrine to be sufficient to indicate a break in the bloodline, is there ANY reason to consider what might be the real errors which disprove the claim to be the “one true church”.
Or to put it another way since I’m not sure that was understandable, it is only valuable to start arguing over whether specific acts of the Catholic Church show it has lost claim to the “one true church”, if both sides agree that showing such specific acts to be in error would actually make a difference in the claim to be the “one true church”.
I suspect from what I’ve read, but it is only my opinion, that the claim for the Church is that no error exists, but also that no such error would make a difference in the claim to the bloodline.
IN my argument, I use “bloodline” because it’s one word but can be understood to express the idea of the “one true church tracing it’s lineage back to Peter”. I apologize if any other meaning of “bloodline” causes offense.
I wrote this totally fabulous response (trust me) and the confuser ate it, and I had to go to Church. Arrrgh. But it WAS terrific, conclusive, you would have read it and repented immediately.(I don’t know of what, but you would have repented ....)
IF I understand you (always a question) you are in a way entirely right. It is circular. You buy the package on the basis of more or less internal consistency and things of that kind, or not.
It’s like I used to get irritated when people would say, “No Pope has ever taught anything contrary to Church doctrine.” At least at first blush that’s like saying, “No Pope ever breathed in without inhaling.” If he’s TEACHING it, with all the bells and whistles, it IS church doctrine. And in a very attractive (to me) way, PapaBenXVI explicitly says in the intro to his book about Jesus something like,”Hey this is not all official. It’s just me here, thinking out loud.”
So the problem with your hypothetical is that it’s kind of incredible to us. IF it were to happen, it would be an earthquake, that’s fer shur.
The pope in the hypothesis would have to feel like IHS on the Cross, abandoned. We take Vatican I to mean that God protects the pope. If the pope got the idea that he was in error, and became convinced of that idea ... Wow.
Since the system IS circular, it seems the way to attack it is to find reductios ad absurdum, and the two ways to defend it are to demonstrate the internal consistency AND to try to find worse absurdities which woulkd follow from assuming it was wrong.
That’s the best I can do. I hope it’s (a) true and (b) responsive.
(BTW - I have no problem with “bloodline.”)