I didn't say the speech to midwives was infallible. I said you had to believe it because it was a teaching of the pope to the whole Church on a matter of faith and morals (or at least it became a teaching to the whole Church after he published it in the Acta Apostolicae Sedis).
It is a condemned error to say that people are only obliged to accept papal teachings that are infallible. I believe that error is condemned even in Casti Connubii itself.
The "Acta Apostolicae Sedis" is addressed to the whole Church. What the pope publishes in there is binding on all Catholics.
"If he will not hear the Church, let him be to thee as a heathen and a publican." -- Jesus Christ.
Same old un-nuanced nonsense you get from most of the SVs. So what, in the practical order, is the difference between "acceptance" of the Dogma of the Assumption, and then accepting every word of a 10,000-word speech given to a group of midwives? Without any nuance (and you apply none), they're practicaly speaking the same thing.
You use the term "accept" equivocally, making no distinctions whatsoever.
Msgr. Fenton points out the distinctions. Please read them again. There's no absolute philosophical assent expected of the non-infallible teaching of a Pope (much less some long expositions that do not claim to be authoritatively teaching anything), but a conditional assent, which can be withheld if some proposition is proven to be erroneous. Otherwise, you'd have to just power-dump every single word of AAS into the Enchiridion Symbolorum.
When a Pope is going on for 10,000 words about a "new problem" and multiple times referring to "two hypotheses", before a group of midwives, this doesn't even rise to the leve of an Encyclical Letter, and even about those Msgr. Fenton explains, you have to read the language to determine the intention of the Pope to engage his authority to teach the Universal Church. It's not uncommon for these Encyclicals to go on for hundreds of pages of expository prose where there's explanation of various concepts but no actual teaching taking place.
Please explain the difference between "accepting" a dogmatic definition, and "accepting" every word of an speech given to midwives. This lack of nuance among SVs does as much damage to papal infallibility as the R&R position where anything short of solemn definitions is fair game. There's a nuanced balance between these two extremes that is lost by both sides.