Comment by jcranmer
7 days ago
"the points already made" is what is known as the "bare passive", and yes, it is the passive voice. You can see e.g. https://languagelog.ldc.upenn.edu/nll/?p=2922 for a more thorough description of the passive voice.
As I said elsewhere, one of the problems with the passive voice is that people are so bad at spotting it that they can at best only recognize it in its worst form, and assume that the forms that are less horrible somehow can't be the passive voice.
I'm not sure this is a "bare passive" like the beginning of "The day's work [being] done, they made their way back to the farmhouse," one of the bare-passive examples at your link. An analogous construction would be, "The points already [being] made, I ceased harassing the ignorant". But in "In addition to the points already made" this case "the point already made" is not a clause; it's a noun phrase, the object of the preposition "to". Its head is "points", and I believe that "made" is modifying that head.
Can you insert an elided copula into it without changing the meaning and grammatical structure? I'm not sure. I don't think so. I think "In addition to the points already being made" means something different: the object of the preposition "to" is now "being", and we are going to discuss things in addition to that state of affairs, perhaps other things that have happened to the points (being sharpened, perhaps, or being discarded), not things in addition to the points.
"In addition to the points that have already been made"
I agree that that has the same meaning, but I think it may have a different grammatical structure, with an entire subordinate clause that was missing from the original. Since the voice of a verb is a grammatical rather than semantic question, this seems relevant; "in addition to the points people have already made" is also (probably) semantically equivalent but unquestionably uses the active voice.