Natural Operations Remain

Aquinas asks whether the sacramental species can nourish.

His answer is yes. The species can nourish and undergo corruption because the accidents retain their natural operations by divine power.¹

This is the chapter’s careful bridge.

It would be sloppy to say Aquinas had a modern concept of calories, insulin, or glycemic index. He did not.

It is fairer to say that he preserved the bodily operation of the species. What looks and acts as bread can still nourish like bread.

That matters for the later wheat question. Catholic doctrine does not make the host metabolically irrelevant. It makes the host metaphysically Christ while the species remain bread-like in bodily operation.

This is subtle. The Eucharist is not being reduced to nutrition. The doctrine itself makes room for natural effects.

Related sections: Substance Accidents Species; Lateran And Aquinas.