This thread is wandering way off-target. Can we forget about who’s a JW and the evils of birth control. I’d really like an answer to my original questions.
No problems. However, it’s necessary, I think, to remind everyone: we tend to get too caught up in the question “is this teaching
infallible?”, when really, the question is “is this teaching,
infallible or not, something that the Church is putting before me with the obligation that I listen and obey it?” … and the answer to
that question is yes: whether a teaching is infallible or not, the official teachings of the Church are to be obeyed, and not debated as if there are ‘optional’ doctrines, dogmata, or disciplines.
Now, to your question, Gary. The first two seem to already have been answered sufficiently well:
We need Church councils because, although the pope may make infallible statements, there’s a college of bishops who share in the Apostolic succession. If Jesus had said, “ok, guys, I’ve got Peter now, so the rest of you can just go home and relax,” then you’d be able to argue the “just ask the pope” approach. Since He didn’t, then it’s appropriate to utilize the college of bishops in their magisterial role for ordinary expressions of the magisterium.
Papal infallibility
hasn’t only been used twice, although, in terms of what most people think of as 'teachings on faith and morals," it’s been used twice in recent history, in the general era surrounding the formal definition of ‘infallibility.’
Excuse me if I’ve missed it, but I haven’t seen an answer to your third question:
I keep hearing that “Unam sanctam”, a papal bull written in 1302 by Pope Boniface VIII is not considered infallible yet it says: “Furthermore, we declare, we proclaim, we define that it is absolutely necessary for salvation that every human creature be subject to the Roman Pontiff.” How could this not be considered to be intended as an infallible declaration?
What people are saying, I think, is that people need to understand the context of
Unam Sanctam, so that they don’t just proof-text its final line and mistakenly interpret what it’s saying (and what it’s not!). In its historical context, we see that secular leaders (i.e., kings) were telling the pope “we’re both leaders, but
I’m in a superior position than you” or “I’m a secular leader, so I have primacy over you in secular matters.” The practical upshot was that world leaders were telling the Pope “I don’t like what you’re saying, and
I don’t have to listen to you,” and, therefore, “I’m not committing a sin when I disobey the Pope.”
In response to these kinds of assertions, Boniface VIII wrote
Unam Sanctam to refute their arguments and re-assert that Christian leaders
were required to obey the Pope; that is, that they couldn’t claim a carte blanche exception to papal authority based on their own secular authority. With that in mind, the pope replied, “no, I
do have authority over you, and if you disobey me, you
are at risk of committing sin and losing your salvation.”
With that in mind, we can progress to the question “is this teaching infallible?”. Inasmuch as it answers the question, “does there exist a (Catholic) world leader who does not have to obey the pope due to his secular position?”, the answer, it would seem, is “yes, it’s an infallible teaching on the faith.” (However, if you want to be anachronistic and recast it as if it said, “do all people – Catholic or not – have to obey the pope or lose their salvation?”, then I’d have to reply that this phrasing is
not an infallible statement… since it isn’t at all the statement that Boniface VIII was making.

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