When do popes speak ex cathedra?

Considerfour groups that, one might think, couldn’t be more different: Pope Francis’s mostzealous defenders; sedevacantists; Protestants; and Catholics who have recentlyleft the Church (for Eastern Orthodoxy, say). Something at least many of them have in common is a seriousmisunderstanding of the Catholic doctrine of papal infallibility – one whichhas led them to draw fallacious conclusions from recent papal teaching thatseems to conflict with traditional Catholic doctrine (for example, on HolyCommunion for those in invalid marriages, the death penalty, and blessings forsame-sex couples).  Some of PopeFrancis’s defenders insist that, since these teachings came from a pope, they must therefore be consistent with traditionaldoctrine, appearances notwithstanding. Sedevacantists argue instead that, given that these teachings are notconsistent with traditional doctrine, Francis must not be a true pope.  Some Protestants, meanwhile, argue that sinceFrancis is a true pope but the teachings in question are (they judge) notconsistent with traditional Christian doctrine, Catholic claims about papalinfallibility have been falsified. Finally, some Catholics have concluded the same thing, and left theChurch as a result. 

I’ve addressedthe doctrinal controversies in question at length elsewhere and will notrevisit them here.  The point for presentpurposes is that, whatever one thinks of them, none of these inferences issound, because they rest on the false assumption that Catholicism claims that apope could not err in the ways Francis is in these cases alleged to haveerred. 

The Church’steaching, as famously defined at the FirstVatican Council, is as follows:

When the Roman Pontiff speaks ex cathedra, that is, when, in the exercise of his office as shepherd and teacherof all Christians, in virtue of his supreme apostolic authority, he defines adoctrine concerning faith or morals to be held by the whole Church, hepossesses, by the divine assistance promised to him in blessed Peter, thatinfallibility which the divine Redeemer willed his Church to enjoy in definingdoctrine concerning faith or morals.

It is fairlywidely understood that this does not mean that a pope is impeccable in hispersonal moral behavior, or that he cannot err when he speaks on some topicunconnected to faith or morals, or that he cannot err when he offers a personalopinion on some theological matter rather than teaching in his capacity as pope.  Rather, it is only when speaking as universalpastor of the Church on a matter of faith or morals that he is infallible.

However, whatis somewhat less widely understood is that even this is not enough for aninfallible ex cathedra statement.  As the passage from Vatican I says more thanonce, the pope also needs to be speaking to the universal Church on a matter offaith or morals in a manner that definessome point of doctrine.  And to “define”a doctrine is more than just putting it forward as binding on thefaithful.  As the Second Vatican Councilteaches in LumenGentium, even papal teaching that is not ex cathedra is normally binding (though as I’ve discussed elsewhere,the Church acknowledges rare exceptions). To define a doctrine involves, in addition, putting it forward in an absolutely final, irrevocablemanner.  When a pope defines some pointof doctrine, he is teaching it in a way that is intended to settle the question for all time and can never be revisited.  It only when speaking with this maximum degree of solemnity that a popeis claimed by Vatican I to be making an infallible ex cathedra pronouncement. 

Suchpronouncements are rare, and Pope Francis has never made one.  In particular, none of the doctrinal controversiesreferred to above involves any such pronouncement.  Neither AmorisLaetitia’s teaching on Holy Communion for those in invalid marriages, northe 2018 revision to the Catechism on the topic of capital punishment, nor Fiducia Supplicans’s teaching onblessings for same-sex couples, involves any ex cathedra statement.  Noneof these documents is intended to “define” or settle in an absolutelyirrevocable way any doctrinal matter.  Hence,if one or more of them really does contain doctrinal error, that would be –though regrettable and indeed scandalous – nevertheless compatible with thedoctrine of papal infallibility, because none of them is the kind ofpronouncement that is covered byinfallibility.

Hence, noneof the inferences referred to above is sound. The fact that these doctrinal pronouncements were issued under thepope’s authority does not (contraryto some of Pope Francis’s defenders) byitself guarantee that they must be reconcilable with tradition, becausethey are not ex cathedra definitions.  Nor, if they are erroneous, would that entailthat Francis is not a true pope, since (contrary to what some sedevacantistsseem to think) even true popes are not infallible when teaching in the specific manner of the documentsin question.   For the same reason – andcontrary to what some Protestants and some Catholics who have lost their faithsuppose – if Francis has erred in these cases, that would not falsify Catholicclaims about papal infallibility, because the Church never claimed in the firstplace that popes are infallible when making pronouncements of the specific kind in question, since none of them involves anattempt at making an ex cathedradefinition.

The teaching of the manuals

It isimportant to emphasize that this is in noway some novel interpretation of papal infallibility manufactured in orderto deal with the controversies that have arisen during the pontificate of PopeFrancis.  It is simply the way Catholictheologians have always understood the matter. To see this, consider what is said in several standard theology manualsof the period between Vatican I and Vatican II. This was, of course, the period when the popes were most keen toemphasize their power to settle matters of doctrine.  And yet the manuals say exactly what I justsaid about the conditions on an excathedra statement.  It is worthadding that these are manuals that received the Nihil Obstat and Imprimatur.  That does not entail that they areinfallible, but it does mean that what they say was regarded by ecclesiasticalauthorities as perfectly orthodox and unremarkable. 

Let’s beginwith Scheeben’s 1874 Handbookof Catholic Dogmatics, Book One, Part One.  Commenting on papal authority infallibly tojudge matters of doctrine, it tells us that “only those propositions orconsiderations which the judge evidently intendedto determine peremptorily are to be regarded as judicially determined andthus infallibly true” (p. 331, emphasis added). That is to say, unless the pope intends to settle a matter in aperemptory or final way, his pronouncement is not of an ex cathedra nature. Accordingly, Scheeben says, “it is possible, notwithstanding thecontinuing operation of his authority, that the pope extra iudicum [i.e. not excathedra] should profess, teach, or attest something false or heretical” (p.144, parenthetical remark in the original).

Brunsmannand Preuss’s 1932 Handbook of FundamentalTheology, Volume IV, tells us the following:

An ex-cathedra decision…implies the unmistakable intention of the pope to utter a definitive andbinding doctrinal decision and to oblige the Universal Church to accept it withabsolute certainty.  Hence if the pope,even in his capacity as supreme shepherd and teacher, were to recommend to allthe faithful a certain doctrine regarding faith or morals, even if he commandedthat doctrine to be taught in all the schools, this would be no ex-cathedra definition, because no definitive doctrinaldecision would be intended.  The case issimilar with regard to decrees issued by the Roman congregations, when they (ashappens with the S. Congregation of the Holy Office, over which the popehimself presides) condemn a doctrine, and the decision is confirmed by thesupreme pontiff and published by his authority. Such decrees are not per se infallible… If and so long as there is areasonable doubt whether the pope intends a definition to be ex cathedra, no one is in conscience bound to accept itas such.  (pp. 49-50)

Notice thatBrunsmann and Preuss not only note that a papal pronouncement does not count asex cathedra if it is not intended as“definitive” and as settling the matter with “absolute certainty,” but alsooffer specific examples of teaching that would, accordingly, not count as ex cathedra.  Even a doctrine that a pope in his capacityas universal teacher commends to all the faithful and commands to be taught, ora doctrine taught with his approval by the Holy Office (now known as theDicastery for the Doctrine of the Faith), would not count as ex cathedra unless there were an “unmistakable intention” and no “reasonable doubt” that he intendedit as an absolutely final and irrevocable doctrinal definition.

Ludwig Ott’s1955 Fundamentals of Catholic Dogmasays:

Not all the assertions of theTeaching Authority of the Church on questions of Faith and morals areinfallible and consequently irrevocable. Only those are infallible which emanate from General Councilsrepresenting the whole episcopate and the Papal Decisions Ex Cathedra.  The ordinary and usual form of the Papalteaching activity is not infallible. Further, the decisions of the Roman Congregations (Holy Office, BibleCommission) are not infallible. (p. 10)

The condition of the Infallibility isthat the Pope speaks ex cathedra.  Forthis is required… that he have the intention of deciding finally a teaching ofFaith or Morals, so that it is to be held by all the faithful.  Without this intention, which must be madeclear in the formulation, or by the circumstances, a decision ex cathedra isnot complete.  Most of the doctrinalexpressions made by the Popes in their Encyclicals are not decisions excathedra. (p. 287)

Ott herereiterates the points we’ve already seen in the other manuals, and adds that“the ordinary and usual form” ofpapal teaching, including “most of thedoctrinal expressions… [in] Encyclicals,” are not infallible. 

Salaverriand Nicolau’s 1955 SacraeTheologiae Summa, Volume IBnotes that “to speak ex cathedra,according to Vatican I, implies that the Roman Pontiff teaches something… defining it as something that must be held,that is, obliging all to an absolute assent of the mind and deciding the matter with an ultimate andirrevocable judgment” (p. 216, emphasis in original).  They add that “the manifest intention of defining something is required” (p. 219,emphasis added).  In other words, and asthe other manuals note, unless a pope explicitly tells us that he intends tosettle some doctrinal matter in an absolutely final and irrevocable way, wedon’t have an ex cathedra definitionand thus don’t have an infallible pronouncement.

Van Noort’s1957 Dogmatic Theology, Volume II:Christ’s Church comments on the matter at length:

The pope, even acting as pope, canteach the universal Church without making use of his supreme authority at itsmaximum power.  Now the Vatican Councildefined merely this point: the pope is infallible if he uses his doctrinalauthority at its maximum power, by handing down a binding and definitivedecision: such a decision, for example, by which he quite clearly intends tobind all Catholics to an absolutely firm and irrevocable assent.

Consequently even if the pope, andacting as pope, praises some doctrine, or recommends it to Christians, or evenorders that it alone should be taught in theological schools, this act shouldnot necessarily be considered an infallible decree since he may not intend tohand down a definitive decision.  Thesame holds true if by his approval he orders some decree of a sacredcongregation to be promulgated; for example, a decree of the Holy Office…

For the same reason, namely a lack ofintention to hand down a final decision, not all the doctrinal decisions whichthe pope proposes in encyclical letters should be considered definitions.  In a word, there must always be present andclearly present the intention of the pope to hand down a decision which isfinal and definitive…

[W]hen he is not speaking excathedra… All theologians admit that the pope can make a mistake in matters offaith and morals when so speaking: either by proposing a false opinion in amatter not yet defined, or by innocently differing from some doctrine alreadydefined.  (pp. 293-94)

Van Noortgoes on to give an example of a case where a decree of a sacred congregationwas issued with papal approval but turned out to be doctrinally erroneous:

It should be candidly admitted, wethink, that the sacred congregation did condemn Galileo’s teaching by what wasactually a doctrinal decree. The opinion of some theologians that the decree… was a purely disciplinary decree… is, in our opinion, difficult tosquare with the facts of the case. Likewise it should be frankly admitted that the Congregations of theInquisition and of the Index committed a faux pas in this matter…

The pope was aware of the decree ofthe congregation, and approved it as a decree of the congregation. (pp. 308-9)

Van Noort’sdiscussion repeats the points made in the other manuals, and adds the positiveexplicit assertion that “the pope can make a mistake in matters of faith andmorals” when not speaking ex cathedra,along with an example in which a Vatican congregation acting with papalapproval did in fact issue a mistaken doctrinal decree.

Again, thesemanuals were all written afterVatican I proclaimed papal infallibility but before Vatican II and the doctrinal controversies that arose in itswake.  Hence no one can claim that theyreflect some more limited, pre-Vatican I conception of papal authority.  Nor can anyone claim that they reflect thepolemical interests of post-Vatican II progressives or traditionalists who, forvery different reasons, would want to emphasize the limits of papal power.  They are also exactly the sorts of manualssedevacantists like to appeal to in support of their position.  But in fact they undermine that position,because they show that the errors sedevacantists accuse the post-Vatican IIpopes of would (even if these popes really were guilty of all the errors theyare accused of) be errors of precisely the kind the Church acknowledges canoccur, consistent with what Vatican I says about the conditions oninfallibility.

Again, I’mnot going to revisit here the details of the doctrinal controversiessurrounding Pope Francis.  But if the pope’s exhortation Amoris Laetitia, the 2018 revision tothe Catechism, or the DDF declaration FiduciaSupplicans contain doctrinal error, then these would be the kinds of errorsthe Church acknowledges to be possible for a pope to make, because none of themis an ex cathedra pronouncement.  Hence they would not falsify Catholicism, norwould they show that Francis is not a true pope.

A heretical pope?

But whatabout the thesis that a pope might lose his office due to heresy, which wasdiscussed by St. Robert Bellarmine, Francisco Suárez, and others among theChurch’s great theologians?  The firstthing to say here is that what is in view in this thesis is formal heresy, not mere material heresy.  A material heresy is a claim that is in factheretical in its content, whether or not the person who asserts it realizesthat, or would persist in adhering to the claim after being warned that it isheretical.  A person who holds some viewthat is materially heretical would not for that reason alone sufferexcommunication and thus cease to be a Catholic.  That would happen only as a result of formal heresy, which is a materialheresy that a person persists in despite the attempts of ecclesiastical authorityto correct him.  Moreover, we have to becareful in determining what counts as “heresy,” which in canon law is not justany old theological error, but specifically the denial of some teaching thatthe Church has officially defined.  A formal heretic, then, is someone whoobstinately denies some doctrine that the Church has formally defined, despitethe attempt of the Church to correct him.

The thesisin question is that if a pope were a formal heretic in this sense, he wouldcease to be a Catholic, and thus cease to be pope, since a non-Catholic cannotbe a pope.  But as Ihave argued elsewhere, no one has succeeded in showing that PopeFrancis is a formal heretic.  So the thesisthat he might have lost his office due to formal heresy is moot.  But even if he were a formal heretic, thematter is still nowhere near as straightforward as sedevacantists suppose.  For one thing, the thesis that a pope couldlose his office for formal heresy is not a teaching of the Church, but atheological opinion, nothing more. Whether a pope really could become a formal heretic, and, if so, whetherhe would lose his office, are matters that have been debated but never settled,either by theologians or by the Church. 

Here is whatVan Noort says on the matter:

Thus far we have been discussing Catholic teaching.  It may be useful to add a fewpoints about purely theological opinions…Theologians disagree… over the question of whether the pope can become a formalheretic by stubbornly clinging to anerror on a matter already defined.  Themore probable and respectful opinion, followed by Suárez, Bellarmine and manyothers, holds that just as God has not till this day ever permitted such athing to happen, so too he never will permit a pope to become a formal andpublic heretic.  Still, some competenttheologians do concede that the pope when not speaking ex cathedra could fallinto formal heresy.  They add that shouldsuch a case of public papal heresy occur, the pope, either by the very deeditself or at least by a subsequent decision of an ecumenical council, would bydivine law forfeit his jurisdiction. Obviously a man could not continue to be the head of the Church if heceased to be even a member of the Church. (pp. 293-94)

Salaverriand Nicolau write: “Theologians concede that a general Council can licitlydeclare a Pope heretical, if this case is possible, but not to depose himauthoritatively since he is superior to the Council, unless it is clearlycertain that he is a doubtful Pope” (p. 217).

Note firstthat both manuals are tentative about whether it really is even possible for apope to become a formal heretic, though some theologians do allow that this ispossible.  There are two lessons to drawfrom this that are relevant for present purposes.  The first is that the Church does permittheologians to entertain and debate the possibility that a pope may not onlyerr, but even fall into formal heresy.  This is important for properly understandingthe doctrine of papal infallibility, because it shows that the Church is veryfar from claiming that everything apope might say on matters of faith or morals is infallible.  Second, though, the common opinion is thateven if a formally heretical pope is possible in theory, it is highly unlikelythat divine Providence would allow this ever in fact to occur.  And this reinforces a point that should beobvious in any event, which is that a Catholic ought to be extremely cautious about accusing a pope of formal heresy, asopposed to some lesser degree of error. 

But it is,in any event, not up to just any old Catholic with a stack of theology manualsand a Twitter account to make this determination.  Note that the manuals make reference to theaction of a council against a popeguilty of formal heresy.  For to whomdoes the task fall to warn a pope that he is in danger of such heresy?  And who has the authority to decide that,after having been warned to no avail, his heresy is obstinate and thus has infact passed from being material to being formal?  If just any old Catholic could claim theright to do this, the result would be precisely the sort of chaos that theinstitution of an authoritative hierarchical Church is supposed toprevent.  Hence the common view is that, if a pope were to fall into formalheresy and if he were to lose hisoffice as a result, the latter could only occur after some authoritativeecclesiastical body had made the juridicaldetermination that he had in fact fallen into formal heresy and ipso facto lost his office.

Yet eventhis, as Ihave argued elsewhere, would by no means solve all the problems thatarise in such a scenario.  And thisreinforces the point that we are dealing here not with any actual teaching of theChurch, but with highly controversial and problematic theological theories,albeit ones the Church permits us to speculate about.  And it is merely on such speculative theories, rather than on official Catholic doctrine,that the sedevacantist position is grounded. 

Ex cathedra heresy?

So far wehave been discussing papal teaching that is not presented in the first place asif it were an irrevocable ex cathedrapronouncement.  But what if a popeattempted to teach some heresy in an excathedra way?  Is this possible evenin theory?  Sometimes Catholics saythings to the effect that were a pope ever to try to do this, God would strikehim dead before he could carry it out. Interestingly, though, Scheeben treats the matter as being morecomplicated than that.  He writes:

Infallibility in itself does notabsolutely rule out the possibility that the judge oflast resort may place… a formally invalid act of judgment.  In this sense, therefore, many theologians inthe Scholastic period were able to deem the judicial infallibility of the popeconsistent with the possibility that he, out of wantonness or fear, might placepersonal acts, even with the claim of his authority, which should not beregarded at the same time as acts of his authority or of his See and hence,without prejudice to the infallibility of the latter, could be erroneous.

Those theologians considered… thesole [hypothetical] case of obvious and absolute temerity the one in which thepope would attempt to define a notorious heresy, or, what amounts to the same thing, to reject a notoriousdogma that is held withoutdoubt by the entire Church and thus to require the whole Church to abandon herfaith; for in this case, they said, the pope would behave not as a shepherd but as a wolf, not as a teacher but as a madman, whileon the other hand the Church or the episcopate could and would have to rise upimmediately as one against the pope, although we could not say thatshe was rising up over or even merely against papal authority; rather she would rise up only against the arbitrariness of the person whohitherto had possessed the papal authority, but plainly through thequestionable act renounced it and relieved himself of it. (p. 310)

WhatScheeben appears to have in mind by a “notoriousheresy” or the “reject[ion of] a notorious dogma” is the explicit denial ofsomething manifestly previously definedas irreformable doctrine.  And by the“attempt to define” such a heresy, Scheeben seems to have in mind a case wherea pope issued a decree like the following: “Using my full authority assuccessor of Peter and universal teacher of all the faithful, I hereby declareand define by a solemn and irrevocable decree that Jesus of Nazareth was notthe Son of God,” or something similarly manifestly heretical. 

Scheebendoes not claim that Providence might ever in fact allow such a thing, but hedoes discuss it as an abstract possibility that would not be strictly ruled outby the doctrine of papal infallibility. But how could it not be ruled out? Scheeben’s view (or at least, the view of the Scholastic theologians hehas in mind) is that such an act would be “formally invalid” precisely because it would manifestly conflictwith previously defined dogma.  The ideaseems to be that among the conditions on an excathedra definition is that it be logically consistent with previousdefinitions.  After all, when proclaimingpapal infallibility and setting out the conditions on ex cathedra pronouncements, Vatican I explicitly says that:

The Holy Spirit was promised to thesuccessors of Peter not so that they might, by his revelation, make known somenew doctrine, but that, by his assistance, they might religiously guard andfaithfully expound the revelation or deposit of faith transmitted by theapostles.

The positionScheeben is describing, then, would seem to be that an attempt to define amanifest heresy ex cathedra would bea kind of misfire, a failure right from the get-go to fulfill a basic conditionon making an ex cathedra definition –just as a failure explicitly to speak in one’s capacity as pope, or a failureto manifest one’s intention actually to define a doctrine irrevocably, would bea failure to fulfill the conditions on an excathedra pronouncement.  (In thisrespect, the position Scheeben is describing would be analogous to Fr. ThomasWeinandy’s thesis about the conditions on magisterial teaching more generally,which I discussed in arecent post.)

Some mightobject to this position (as some have objected to Fr. Weinandy’s thesis) thatit amounts to an appeal to “private judgment,” the very thing Catholicscriticize Protestants for.  For if aCatholic were to judge some papal definition heretical, wouldn’t this preciselybe to rely on his own judgment rather than that of the Church?

But thisobjection rests on a crude misunderstanding of the notion of “private judgment.”  The Church has never claimed that we have no understanding at all of scripture,tradition, or past papal teaching apart from what the current pope happens tosay about it.  And such a claim would bemanifestly false.  You don’t need thepope to tell you, for example, that scripture teaches that God created theuniverse, that he made a covenant with Israel through Moses, that Jesus claimedto be the Son of God, and so on. Non-Catholics no less than Catholics can know that much just from reading the Bible and noting how it has alwaysbeen understood for millennia.  It’s notas if the text is just a bunch of unintelligible squiggles that we can makeabsolutely no sense of unless the current pope tells us: “This is what thissquiggle means, this is what that squiggle means, etc.” 

What theMagisterium of the Church is needed for is to settle matters that go beyond what the text has always beenunderstood to say – finer points of interpretation, implications for doctrinalcontroversies, applications to current problems, and so on.  For example, it is open to the Church to say:“This is what divine creation of the universe amounts to,” or “Here is theright way to reconcile this passage with that one.”  It is notopen to the Church to say: “Actually, God did not create the universe afterall,” or “It turns out that we’ve always been misunderstanding scripture whenwe took it to be saying that God created the universe.” 

To deny thiswould be to empty of all content theChurch’s claim to her own infallibility. It would be to say, out of one side of one’s mouth, that the Churchalways teaches in accord with scripture and tradition – but then, out of the otherside, effectively to take this back by saying that if the Church ends upcontradicting some teaching that has always been regarded as part of scriptureand tradition, then it must not reallyhave been part of scripture and tradition after all.  That would be an instance of what is known inlogic as a “No true Scotsman” fallacy.  Itwould make the Church’s claim to infallibility unfalsifiable.

Furthermore,as Ihave shown at length elsewhere, the Church has always acknowledgedthat it can in some cases be legitimate respectfully to criticize popes, evenon doctrinal matters.  The Church couldnot have done so if every criticismof papal teaching necessarily amounted to “private judgment.”

So, Scheebenis correct to hold that, if a pope were to try to define ex cathedra a claim like “Jesus of Nazareth was not the Son ofGod,” that would be a manifest heresy, and it would not amount to “privatejudgment” to say so.  On the contrary, itwould be precisely to adhere, not to one’s own private judgment, but to whatthe Magisterium itself has in the past always insisted is irreformableteaching.

But nowanother objection to Scheeben’s thesis (or rather, the thesis he isentertaining) might arise.  For doesn’tthis thesis itself also make thedoctrine of papal infallibility unfalsifiable? For doesn’t it amount to saying that popes always speak infallibly whenmaking an ex cathedra pronouncement –but then going on to insist that if they do utter some error in what purportsto be an ex cathedra pronouncement,it must not really have been an ex cathedra pronouncement after all?

But that isnot in fact what Scheeben says.  What hesays is that if a pope attempts to define excathedra some “notorious heresy,”then in that sort of case it wouldnot amount to a genuine ex cathedraact but rather only to a failed attempt at such an act.  Again, he evidently has in mind cases where apope would deny some doctrine that has manifestlybeen formally defined by the Churchas irreformable doctrine (for example, the teaching that Jesus is the Son ofGod).  But Scheeben does not addresscases where a pope might attempt to define excathedra some heresy that is notnotorious or blatant, but more subtle.  Andhere, one might argue, is where the doctrine of papal infallibility might openitself to falsification even if one accepts the thesis discussed by Scheeben.

Here wouldbe an example.  Suppose a pope were toattempt to make an ex cathedradefinition like one of the following: “Using my full authority as successor ofPeter and universal teacher of all the faithful, I hereby declare and define bya solemn and irrevocable decree that the death penalty is intrinsically evil,” or “Using my full authority as successor ofPeter and universal teacher of all the faithful, I hereby declare and define bya solemn and irrevocable decree that same-sex sexual activity can be morallyacceptable.” 

Suchpronouncements would not contradict any past formal doctrinal definition – a previous ex cathedra papal pronouncement, a conciliar definition, or thelike.  But they would manifestly contradict the clear and consistent teaching ofscripture and of the ordinary magisterium of the Church for two millennia.  And the Church holds that scripture and theconsistent teaching of the ordinary magisterium cannot be in error on a matterof faith or morals.  Hence, if a popeattempted to make an ex cathedrapronouncement of one of the kinds just described, he would clearly be teachingerror.

Hence, Iwould say, if a pope were to make such a pronouncement, that would falsify the doctrine of papal infallibility.  And I am myself not inclined to agree withthe thesis entertained by Scheeben either. That is to say, I am inclined to say that, if a pope tried to define ex cathedra a “notorious heresy” likethe claim that Jesus was not the Son of God, that too would falsify thedoctrine of papal infallibility.

Since I haveno doubt that that doctrine is true, I would predict that such a thing will neverin fact happen.  The doctrine isfalsifiable in the sense that it makes substantive empirical claims that can betested against experience.  But it haspassed every such test for two millennia, and will continue to do so.

Relatedposts:

Whendo popes teach infallibly?

Popes,heresy, and papal heresy

Whatcounts as magisterial teaching?

TheChurch permits criticism of popes under certain circumstances

Aquinason St. Paul’s correction of St. Peter

Papalfallibility

Theerror and condemnation of Pope Honorius

CanPope Honorius be defended?