> Papal doctrine is the word of God until a subsequent pope says otherwise
No, that’s Hyperpapalism, which is an error.
The Pope does not have the authority-power to transform error into truth, nor can he make “new truths” (of the Faith), whatever that might mean. He does have the solemn duty to faithfully hand on and explain the Apostolic Tradition. In an extra-ordinary act of his office, the Pope can, without error, define the proper understanding of Catholic teaching on a matter of faith or morals.
In the case of John XXII he proposed something false as pertains to Catholic doctrine, repeatedly, in public sermons. He was rebuked for it and recanted before he died. What he taught was not somehow “intermittently true”, it was an error through and through, and it was completely right that his subjects called him out on the matter.
> The Pope does not have the authority-power to transform error into truth,
The problem with your argument is that it is "left as an exercise for the reader" to determine what is actually true. If that were the case, then the Pope, as the representative of God on Earth, serves no purpose: everyone can individually determine what is true and what is an error. That does not agree historically with the role of the papacy.
If everyone has a right to their own interpretation of doctrine, what does the Pope do, and why should anyone listen to him?
Your position that absolute faith in the word of the pope
is a fallacy is itself a self-supporting fallacy, which you hold only because you don't believe in the correctness of the pope.
> he taught was not somehow “intermittently true”
Yes, it was. God would not allow a Pope who spoke in error.
a few comments back, you stated a Catholic must accept the pope's interpretation; I think this is generally true?
The problem here is, we're saying the person who claims to be pope has contradicted past teachings that popes infallibly taught already. So the only way out then would be to consider they were never popes in the first place or else you have the contradiction of a pope taught error or that the pope is not infallible.
For example in Dignitatis Humanae (Declaration on Religious Liberty) in the Vatican 2 documents it states: "This Vatican synod declares that the human person has a right to religious freedom. Such freedom consists in this, that all should have such immunity from coercion by individuals, or by groups, or by any human power, that no one should be forced to act against his conscience in religious matters, nor prevented from acting according to his conscience, whether in private or in public, within due limits."
This is obviously contrary to the Catholic understanding of conscience and coercion - the "due limits" and "religious freedom" are never defined, when they were already somewhat clearly defined.
Hence being ambiguous, we would understand these in themselves to not be Catholic teachings. Consider if someone asked a person if they are a Catholic and they answered "I am a Christian". In itself, their answer does not explain if they are Catholic or not: some Catholics might argue that "only Catholics are Christians" and that the statement could mean "I am a Catholic"; some protestants might argue that "only non-Catholics can be Christians" so that the statement means "I am not a Catholic". Hence, in itself the statement is "objectively ambiguous" - the Vatican 2 statements are of this character, and if you had to categorize them as either "Catholic or not", it seems they would resolve to being considered as "clearly not Catholic". In any event, it seems we would be forced to reject the language as it stands and new documents that are clearer would have to be drawn up and agreed to.
For example, a person does not have the right to declare they have the "religious freedom" to be a "Pirate" and that they are free to steal from other people "conscientiously"; they are allowed to be "coerced" to not steal, if they try to steal.
Regarding John XXII from the other comment, I believe St. Robert Bellarmine in De Romano Pontifice examined all cases of alleged papal heresy and explained why no popes had been heretics. John XXII simply speculated as a private theologian about an issue that had not been defined by the Church yet, hence did not enter in to error in doing so.
No, that’s Hyperpapalism, which is an error.
The Pope does not have the authority-power to transform error into truth, nor can he make “new truths” (of the Faith), whatever that might mean. He does have the solemn duty to faithfully hand on and explain the Apostolic Tradition. In an extra-ordinary act of his office, the Pope can, without error, define the proper understanding of Catholic teaching on a matter of faith or morals.
In the case of John XXII he proposed something false as pertains to Catholic doctrine, repeatedly, in public sermons. He was rebuked for it and recanted before he died. What he taught was not somehow “intermittently true”, it was an error through and through, and it was completely right that his subjects called him out on the matter.