This, to me, is the real crux of the matter.
The first problem is in saying that it is not the meaning of “vespere.” That is, when it’s all said and done, the very word used in the canon. It is the one-and-only criteria articulated in the canon. It must be “vespere” (at least with regard to Saturday). …]
To be clearer, the point is not to pull out Lewis and Short and see what “vespere” means in classical or ecclesiastical Latin, divorced from the context of the canon. If the intention of the legislator in using “vespere” was to merely indicate a vague, intentionally unspecified time after midday (and not all “before-4pm-ers” argue for noon; there is at least one other main school saying 2pm), then that the mind of the legislator would indeed determine that, whatever vespere does mean there, it is not going to be determined by figuring out when a Roman centurion believed “evening” to begin. Now, while popes rarely give canonical commentary, the people who wrote the CIC for John Paul II *did * answer the question of their intended meaning - when asked for a clarification from people trying to resolve the issue before us - and it is that intended meaning you dismissed above as mere commentary: “Consulto formula generalis adhibetur ut casuistica et anxietates vitentur.” (Communicationes 15 [1983] 251-252). A “general” (i.e., unspecified) formula is used “intentionally” (consulto). They are not John Paul, whose law it actually is, but they certainly express faithfully the grammatical intention of vespere in the canon. When John Paul refers in Dies Domini to fulfilling the obligation in the “evening,” it should be safe to say that he means by that evening “the time period during which the canons I myself promulgated allow for the fulfillment of the obligation;” but that is a time period that was deliberately NOT specified to begin at 4pm.
When did he say he intended to “modify the timeframe” ?? As far as I can tell, he merely wanted to take something that was an indult and make it into universal law. What justification is there for saying that he intended to modify the timeframe?
The canon allowing fulfillment of the precept on either Sunday OR Saturday modifies the timeframe for fulfillment in two ways. First, it takes what was previously the result of (near-universal?-but-nonetheless-local) indults and made those universal law. So whereas this timeframe used to be, technically, against the canons but allowed as a special favor, the canonical time period itself was modified such that the period covered by the indults now falls within the normative time. Second, it extends the time for fulfilling the precept beyond the course of a single day. It is beyond the course of an ancient Mediterranean day because those run from evening to evening, meaning that logic would exclude Sunday evening Masses (which would belong to Monday). It is beyond the course of a canonical day, which runs from midnight to midnight unless expressly indicated. This expansion beyond the 24-hour period of Sunday (and, indeed, before the 1950s we’re actually talking about more of an 8-hour period when Mass could be said, from roughly 5am-1pm) was enshrined in canon law for the purpose of enabling easier fulfillment of the precept. If a favor is granted, it ought to be interpreted broadly, and though by making this the law itself the indults ceased to be favors, the principle would still seem to hold, especially since the drafters’ intention was non-restrictive.
It has been defined as 4 PM since World War II.
That is exactly why canonists take the position of 4 PM. It wasn’t something just pulled out of thin air. We have 70 years of precedent.
The Korean War, but who’s counting? Call it more than a tidbit, fine, but this precedent is not finally dispositive. It is readily acknowledged by those who argue for an earlier time, but those individuals then go on to say that the 4pm start time that was firmly set for the first decade or so (1953-1966) was relaxed by the indults granted to Spain and Germany in '66, indults conceded “juxta preces” whose internal logic, it is argued, allows for times earlier than 4:00. And even if one were to reject that reasoning, the next backstop on your decades of precedent would be 1983, when the new CIC deliberately chose (at least according to the men who wrote it) NOT to fix the beginning of evening at 4pm. That makes for 30 years during which “vespere” meant “after 4pm” and now slightly more than 30 years during which it meant “during an evening period whose precise beginning is not set exactly by the law - and thus open to prudential application.”
Again, at the end of the day, I think the proponents of an early start have a heavy burden of proof to justify departing from the original 4pm standard. But I make a point of opposing their arguments to yours because these are not tin-hat loonies. They are respected canonists who are not marginalized within the guild for their views. So rather than throw a tizzy about how they must obviously be idiots who never noticed the word “vespere”, we ought to try to understanding their canonical reasoning.