ROME – Journalistic convention dictates that whenever we write about Pope Francis these days, we frame things in terms of his supporters and his critics. In reality that’s a bit misleading, since few people fall entirely into one of those two categories.

Even the most enthused usually can cite a few times they wish Francis had zigged rather than zagged, and even the most alarmed generally have at least something positive to say. Then, of course, there’s another vast pool of Catholics, to whom the question of what they think of a pope wouldn’t even occur.

I recall once asking my late grandfather his opinion of John Paul II, and he looked at me as if I’d solicited his view on the law of gravity: “He’s the pope, for God’s sake!” Conversation closed.

That said, there are undeniably large and vocal constituencies in the Church right now which are aligned, one predominantly skeptical of the Pope Francis revolution and the other ferociously devoted to it.

For that latter camp — who the Italians often call the bergoglisti, in reference to the pontiff’s given name of Bergoglio — a key question making the rounds at the moment is the following: Will he have enough time?

In other words, will Francis be able to implement enough of his agenda before the end comes, so that it won’t be able to be rolled back?

There’s no specific health crisis prompting that anxiety, but Francis did just turn 80 and has himself suggested several times his papacy may not go on terribly long, so one understands the concern.

It was expressed recently, for instance, by Enzo Bianchi, founder of the ecumenical community of Bose in northern Italy and a deep admirer of Pope Francis. (The feeling is mutual, as Francis named Bianchi to the Pontifical Council for Promoting Christian Unity, the Vatican’s top office for ecumenical affairs, in 2014.)

Bianchi published a piece in L’Osservatore Romano, the Vatican newspaper, just before New Year’s, among other things charging that some of the pope’s critics are guilty of “grotesque accusations and insistent polemics.”

What’s interesting for our purposes, however, is the way Bianchi closed the piece.

“Francis, as everyone knows, has stirred much hope and enthusiasm, for which we can only rejoice,” he wrote. “When I listen to so many simple faithful, the impression I get is of hope that the pope will reform just a few essential things, but do it in a way so there’s no going back.”

Obviously, the last line suggests concern that “going back,” at least right now, is still an option.

Even more explicit was a late December piece on the Jesuit-sponsored site Reflexión y Liberación in Chile, written by a veteran priest named Father Faustino Vilabrille Linares, who serves in a series of small rural villages where, he writes, poverty runs so deep there’s not even electricity.

Clearly a big Pope Francis fan, Vilabrille had an explicit request for the pontiff.

“Continue creating cardinals,” he wrote, “until there’s a sufficient number to ensure that when you’re gone, your reform line in the Church will still be assured, and there won’t be the possibility of going back like some want,” he wrote.

For the same reason, Vilabrille also urged Francis to name more like-minded bishops too, to make sure the job gets done.

Of course, we have no way of knowing how much longer Francis will be at the helm. If we take the previous five popes, meaning Pius XII through Benedict XVI (discounting John Paul I, the pope of 33 days), their reigns lasted an average of almost 15 years, so by that standard Francis could still have a good long run.

Though that number is inflated by St. John Paul II’s almost 27-year term, the third-longest in Church history, even without it, the average is still more than 11 years.

Whatever the span turns out to be, we really don’t have to wait  to tackle the question being asked by the bergoglisti, which is whether Francis’s legacy can be “rolled back.” For anyone familiar with a little bit of Church history, the obvious answer is “yes and no.”

The “yes” part is easy.

Certainly, a new pope can bring a different outlook and sense of priorities, which may in some ways represent a break with his predecessor. Those cheering Francis most loudly today, in fact, often do so precisely because they believe he’s a change from the direction set under John Paul II and Benedict.

The Italians even have a phrase for this dynamic: “You always follow a fat pope with a thin one,” they say, by which they mean that often enough over the years, a liberal pope has been followed by a conservative, a traditionalist by a reformer, etc.

In many ways, a conclave almost invites such a cycle, since inevitably the choice shapes up in part as a referendum on the papacy that’s just ended.

Here, however, is the “no” part: Catholicism isn’t a zero/sum tradition, in which veering in one direction for a while means repealing what came before.

Today, for instance, many Catholic progressives feel that Francis is recovering parts of the legacy of the Second Vatican Council (1962-65), which they regard as having been delayed or interpreted away for several decades.

Yet even if that’s true (and many would argue it’s not), the reason Francis has something to recover in the first place is because Vatican II was still there, still part of the Church’s memory and experience.

No, Francis’s papacy is not going to unhappen. People inspired by him are not going to disappear, and his example will continue to be a point of reference long after he’s gone, just as with countless other popes, movements, saints, thinkers, and so on. Their influence may wax and wane, but it’s perpetually open to being revived and reapplied.

In sum: You can’t unring the bell in the Church, but you can add some other bells to the mix. Over time, the collection of all these different impulses generally produces something in Catholicism resembling balance.

Given that, the meaningful question instead is how we’ll see Francis’s legacy once it’s fully formed – and, of course, which new bells the cardinals who will assemble one day in the Sistine Chapel decide to ring.