B. Scotus’ own Opinion

432. I say, then, to the question that accidents proper to the Eucharist can be corrupted.

433. And this, according to the common opinion [n.150], is sufficiently manifest about the qualities whose change does not require another quantity, because those qualities can be posited as having an abiding common subject, namely quantity.

434. But according to the other opinion [n.151], which posits that the quantity of substance does not differ from substance, nor the quantity of whiteness from whiteness, and consequently that here no quantity is more separate from a subject than the substance of which it is the quantity - according to this opinion it is not equally easy to save the corruption of the quality. For it would then be necessary to posit that any quality is, by equal reason, without a subject, just as also that each of them might change without a subject. And then this position returns to the second difficulty touched on in the preceding question [nn.391-395], how the Eucharist is corrupted by corruption of quantity, and how quantity could be new.

435. However, to the conclusion in general, one could argue as follows: the virtue of an agent is not determined by the fact an accident is without a subject; but if an accident were in a subject, it could be corrupted by a created agent;     therefore etc     .

436. This conclusion does not follow from the reasoning, because the virtue by itself of an equal agent does not suffice, but there is need for it to have a passive object proportioned to it so that it may act as it did before.

437. I reply: as long as the quantity remains, it is easy (according to the common opinion) to preserve a passive object in relation to a natural agent; and this is very possible in regard to contrary qualities, because not every alteration, even between contraries, requires the quantity to change and yet, in such alteration toward quality (with which the species of bread cannot stand), the Eucharist ceases to be; for God has only made institution to conserve the Eucharist (that is, the existence without a subject of the accidents in which is the body of Christ) as long as the qualities remain there that are of a nature to perfect already converted substances. Therefore, the point is simply saved that the Eucharist can cease to be by action of a natural agent. Nor is there any new miracle there, since by the same previous will by which God willed the Eucharist to be in the Church he has also willed that it only remain as long as the qualities would remain that are of a nature to perfect already converted substances.

438. Now as to corruption of the Eucharist by corruption of quantity, statement of what agent it could be done by was made in the preceding question [nn.394-409].

439. And as to whether a new substance must return in conversion of the Eucharist by conversion or change in quantity, statement will be made in the following question [n.490].