I will sum up here the results of the discussion, for which I again thank Scott, as his thougtful and relentless challenge prompted me to study the sources at long last and thus get out of a state of material heresy. (Not the first and probably also not the last, as my road to learning had already been paved with one such temporary state.)

The de fide Catholica doctrine on transubstantiation requires the conceptual framework of substance and accidents. This poses no problem whatsoever to the scientifically-minded Christian, because the notions of substance and accidents are just plain common sense and completely compatible with modern science.

In contrast, that doctrine is completely indifferent to the issue of whether hylomorphism (form and matter) is an adequate conceptual framework to describe purely material entities. Which is very good, because many scientifically-minded Christians, such as myself, think it is not.

Actually, it was precisely an attempt to use hylomorphism what brought me into trouble. Very briefly, I argued that if the soul of Jesus was united to the piece of bread as its substantial form, the consecrated host would have become the body of Jesus. Which would have been really the case, so my thesis did describe a kind of transubstantiation. But it had two critical flaws.

First, since a body is a definite quantity of matter, the consecrated host in this thesis would not have become the "primary" natural body of Jesus, but a secondary "sacramental" body of His. It would still have been informed by his soul, whose Act of Being is the divine Person of the Son, and therefore the whole Christ would have been substantially present. But the situation would have flatly contradicted the words of Institution at the last Supper. Because Jesus did not say just: "this is my body" but: "this is my body, which is given for you." (Lk 22:19). And He did not say just: "this is my blood" but: "this is my blood of the covenant, which is poured out for many for the forgiveness of sins" (Mt 26:28; also Mk 14:24; Lk 22:20). Thus, the blood in the chalice was the same blood which was to be poured out on the next day (or later in the same day, in Jewish reckoning of time). In contrast, in this thesis the consecrated host would not have been Jesus' natural body that was to be crucified, but a secondary "sacramental" body of His, and the chalice would not have held Jesus' natural blood that was to be poured out in his Passion, but a secondary "sacramental" blood of His.

Thus, the thesis was completely unacceptable even before Trent. And as I said, it was not objectively original of mine (though it was subjectively), having been proposed by James of Metz (philosophically active in the first decade of the XIV century) and Durandus of St. Pourcain (c. 1275 – 1332), both of them Dominicans and "critical-Thomists", in the hylomorphic terms that only the substantial form of the bread undergoes conversion, while the primary matter remains unchanged [1].

It was precisely to condemn James' and Durandus' thesis (and therefore also mine, which was its second flaw) that the Council of Trent, in session 13 canon 2, explicitely stated "whole" twice when defining transubstantiation as "that wonderful and singular conversion of the whole substance of the bread into the Body, and of the whole substance of the wine into the Blood-the species Only of the bread and wine remaining-".

Thus, the condemnation at the same canon of the proposition that "the substance of the bread and wine remains conjointly with the body and blood of our Lord Jesus Christ" must be understood in the two possible senses in which the substances of the bread and wine could remain: either at the same level of the substances of the body and blood of Jesus, or as virtual substances existing under them.

Since Trent does not define anything about the compositions of the substances of the bread and wine, but only that nothing of those substances remains after the consecration, the definition of transubstantiation is completely indifferent to the issue of hylomorphism in purely material entities.

Thus, if nothing of those substances remains after the consecration, but only their accidents, (since from the fact that St. Thomas Aquinas uses the terms "species" and "accidents" interchangeably when speaking on the subject [2], it is clear that the bishops at Trent used those terms in the same way,) and "it is manifest that these accidents are not subjected in the substance of Christ's body and blood, because the substance of the human body cannot in any way be affected by such accidents; nor is it possible for Christ's glorious and impassible body to be altered so as to receive these qualities", then "it follows that the accidents continue in this sacrament without a subject" [2].  More precisely, "dimensive quantity (i.e. spatial extension) is the subject of the accidents which remain in this sacrament." [3]

Thus, the very same "natural" Body and Blood of Christ are present in the mode of substance in the spatial extensions of the consecrated Host and Wine, for as long as the accidents of bread and wine remain, and therefore the priest and the faithful do eat and drink the Body and Blood of Jesus. Still, what they touch, taste, chew, etc. are the accidents of bread and wine inhering in that spatial extension, not the Body or Blood of Jesus.

And of course, the soul of Jesus is present as the substantial form of his whole living (Body and Blood), which are together in the host and chalice because they are together in the living Jesus, and his divinity is present as the Act of Being of his soul.

References:

[1] Lowe 2014. "The Contested Theological Authority of Thomas Aquinas: The Controversies Between Hervaeus Natalis and Durandus of St. Pourcain, 1307-1323".
https://books.google.com/books?id=yry2AgAAQBAJ

[2] ST III q. 77 a.1
http://dhspriory.org/thomas/summa/TP/TP077.html#TPQ77A1THEP1

[3] ST III q. 77 a.2
http://dhspriory.org/thomas/summa/TP/TP077.html#TPQ77A2THEP1
 

Last edited by Johannes (8/22/2015 12:00 pm)