@Whoever,
... I'm not quite sure I understand ... if a system of categories is an inventory of all that "is", and what is prior to space and time does not fall within a category, doesn't that amount to saying that what is prior to space and time
is not*? ... and if so, is that truly an assertion that what is prior
is not, or is it just a negative comment on the logical viability of existing systems of categories? ... and what of dynamic categories (process metaphysics) which seem to be able to avoid certain problems that appear to be inherent to substance categories?
(* I hesitate to call it "nothing", as some might consider that a category!) ...