Summa and fallibility

Has the Summa Theologica ever been declared infallible?

A book cannot be declared infallible.

I see. Ok what then about transubstantiation? But then what about Sixtus V’s Vulgate?

what about it?

Perhaps you can elaborate as to what exactly you want to know.

No, because it isn’t.

Right. And beyond that, the Summa is a theological treatise. More than anything it is analysis of Christian teaching using the tools of Philosophy rather than declare teaching itself.

Statements of infallible teaching arise from the magesterium. Ex Cathedra from the Pope, other teaching through the ordinary magesterium. Thomas Aquinas was not a member of the magesterium.

The Summa certainly contains portions that are infallible but they aren’t infallible because they are in the Summa but because they are part of magesterial teaching.

It is NOT infallible, but it is authoritative. The Catholic Church has canonized St. Thomas based on his contributions to Catholic philosophy, which are summarized (Summa) in his seminal work.

And, not only has he been canonized, but he has been elevated to the position of Doctor of the Church (Doctor means teacher). He shares this distinction with only a couple dozen other Saints.

But, he has also been recognized as the Doctor of Doctors (the Angelic Doctor), a distinction that he shares with NOBODY.

While he is not an infallible source of Doctrine, he is an authoritative one. If someone wants to challenge his teaching, that guy ought to have a pretty good argument. Presenting an alternate teaching, and simply dismissing Aquinas because he is not “infallible” will not pass muster. Given the choice between St. Thomas Aquinas, and some guy with a contrary idea but with no philosophical framework, Aquinas will (rightly) win every time.

This is no different than any other field of scholarly study. If someone wants to claim that Mindel was wrong about genetics, or Einstein was wrong about relatively, or that Hubble was wrong about the expansion of the universe, that’s fine - but he had better be prepared to back up his assertion with an alternative that is, at least, equally plausible, or be prepared to present evidence to discredit the established theory.

Thomas tries to explain the Doctrine of Faith as far as they can understood by human reason. As far as the Summa is concerned it is pretty solid intellectually. I have never found an error of reasoning in the Summa. However I have not read all of it. Certainly we are free to disagree with his reasoning. But I don’t think we can disagree with his conclusions since his conclusions always agree with the Doctrine of the Faith.


The “doctrine of faith” then is infallible? I’m not quite sure what that is. Is that what is taught in CCC ?

Sixtus V was going to declare his vulgate as “error free” I guess that would be infallible. The thing was that he was no latin scholar and his Vulgus was full of errors. The night before he was going to declare it error free he died.
They say the Holy Spirit will not let the church teach error. His book was going to be declared infallible and you say a book can’t be declared infallible.

Transubstantiation though is that teachings error free from the church? That the substance of the hosts are the body and blood?

Inerrant and infallible are two completely different things.

That is correct. A book cannot be declared ‘infallible’ any more than a chicken can be declared a rabbit.

I think you are confused. The Pope issued a declaration that it was an authorized version, not that it was error free or infallible. It was authorized, as opposed to the bibles that were UNauthorized like Luther’s translation, etc.

The Real Presence is a dogma of the Church.

So does that mean it’s infallible ?

It is infallibly defined.

I don’t know what you mean. I don’t understand ExCathedra and infallibility.

There is a whole section on it in the Catechism. I would suggest you start there.

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