(2) He speaks of T as a 54-element permutation. There is nothing wrong with that—but Pontifex would work just as well with 64 or 73 or 699 elements, so it makes more sense to describe it as an n-element permutation where n could be 54 or any other integer. I can’t figure out why he settled on 54. Possibly because it is twice the number of letters in the alphabet—but this makes no particular sense.