Contra Pruss on Matter (Part 2)

(This is the second of three blog posts.)
See here for Part 1.

The biggest issue with Pruss’ jettisoning matter is that he throws himself back into the situation of the Presocratics when it comes to substantial change. Pruss wrongly thinks that the issue that the persisting matter is meant to explain is how a corpse looks like the living body, but this isn’t really what is at stake. Rather what is at stake is the very possibility of the generation and destruction of substances.

Given the impossibility (in the natural order at least) of something’s coming from nothing, it is hard to see how substantial change is ever possible once we deny the existence of some matter that persists through the loss of one form and acquisition of another. If the one substance passes away and then in the next moment another substance comes to exist in the same place, it is hard to see how this is a change rather than one thing’s annihilation and another’s creation ex nihilo.

 

First Master of the Bible Historiale of Jean de Berry (fl. ca. 1390),
"'Leaves from Histoire ancienne jusqu'à César"

Pruss’ reasons for thinking that matter cannot be the persisting subject through a substantial change only make sense within a Thomistic understanding of how matter works and even there they fail. He remarks that in the case of death, the corpse has a different parcel of matter from the body before death. First, for thinkers like Scotus that deny that there is only one substantial form in the human body, this problem doesn’t arise at all (others about the unity of the substance do, though). Second, every Thomist thinks that something (the prime matter) persists through death, and so it’s not entirely accurate to say that the parcels of matter are different before and after death. Moreover, a Thomist and really any Aristotelian recognizes that living organisms are composed of potential substances (i.e. the various parts that if separated from the whole would become substances in their own right), and so death for the whole organism means that some of its parts will become short-lived substances on their own. This is clear in the case of a bisected worm where the two havles of the worm are potentially whole worms.

Someone might still worry that if parcels of prime matter only have their identity in virtue of the elemental forms that inhere in them, then it is hard to see how one and the same prime matter can be the persisting subject when it loses one form and gains another. This seems confused. Even if prime matter has its identity by having some form, it can be the same matter despite being informed by different forms. Indeed, it just seems that an efficient cause of a substantial change is what causes the matter to lose one form and gain another.