New popes bring new doctrines, and the canny theologian who is now Pope Benedict XVI has begun making his mark on the Roman Catholic Church by, among other things, speaking in favor of the idea that it is time to make an end to the churchly concept of “Limbo”—putting Limbo in limbo, so to speak. Ordinarily a change in Roman Catholic dogma would hold very little direct significance for most of the readers of a science fiction magazine, but in this case, as I’ll demonstrate in a moment, there’s a definite SF angle. The concept of Limbo got into Catholic terminology by way of St. Thomas Aquinas, the great thirteenth-century theologian, whose primary metaphysical achievement was to reconcile the thinking of the pre-Christian philosophers Plato and Aristotle with the doctrines of the Roman church. (By way of full disclosure: I am not now and never have been any sort of Christian, Roman Catholic or otherwise, and though I’ve read widely in religious texts it has been purely in the spirit of anthropological research, not as a manifestation of belief.) Eight hundred years before the time of Aquinas, an earlier theologian, St. Augustine, had considered the problem of babies who die before they can be baptized. Baptism washes away original sin, the taint brought upon the human race by Adam and Eve, who ate the forbidden apples in Eden. But what about babies who die unbaptized? Augustine concluded that they are, alas, excluded from Heaven and must suffer the torments of Hell along with all other unbaptized souls.

Aquinas found this notion repugnant, as I suppose I would if I believed in Hell in the first place. His solution was Limbo: a place in the afterlife reserved for unbaptized babies—and also the Hebrew patriarchs, Noah, Abraham, Isaac, Jacob, Moses, et al., who were unquestionably persons of virtue but who, because they had lived before the time of Jesus, had been deprived by that technicality of inclusion in the Christian Heaven. According to Aquinas it was unfair to condemn innocent babes to suffer in Hell merely because there had been no time to baptize them, and it was manifestly nonsensical to send the great Biblical patriarchs there. On the other hand, the church taught that baptism was necessary for admission to Heaven, and the babies and the patriarchs had not undergone that rite, so it was impossible to let them in. Limbo was a useful compromise—a place that was neither Heaven nor Hell. (The word “limbo” comes from the Latin limbus, meaning “hem” or “border.”)

The most famous literary reference to Limbo can be found in the fourth canto of Dante’s Inferno, in which Dante, following Virgil, his guide, enters the First Circle of Hell and finds it to be a somewhat revised version of Aquinas’ Limbo. In Dante’s version it seems like a pleasant enough place: there is a meadow, a stream, a seven-walled castle where its inhabitants dwell. The Biblical patriarchs aren’t there, because Jesus had personally descended into Limbo to rescue the lot of them, from Adam and Noah on down, but Dante’s Limbo does contain the souls of other men, women, and children who had lived lives free of sin but had not been able to receive the sacrament of baptism: what Dante calls the “virtuous pagans,” among them Socrates, Plato, Aristotle, the astronomer Ptolemy, the mathematician Euclid, the poets Homer, Horace, and Ovid, the great doctors Hippocrates and Galen, and such well-known figures of the classical world as Cicero, Seneca, and Julius Caesar. A surprising inclusion is the Moslem hero Saladin, Sultan of Egypt in the time of the Crusades, who certainly could have been baptized if he had wanted to, which, of course, he did not. (The lordly Saladin sits in splendid isolation, though if he had cared to have the company of other members of his faith in Limbo he could have sought out the twelfth-century Arab philosopher Averroes, author of a famous commentary on Aristotle, or the third Muslim resident, the physician Avicenna.) Even more astonishingly, Dante also includes in his group of virtuous pagans a remarkable collection of mythical and fictional characters: Orpheus, Hector, Aeneas, and the Amazon queen Pen-thesilea, a character in the Iliad.

Since Dante’s day the church has found the idea of Limbo an embarrassment, not only because it exposed a troublesome conflict between the teachings of the two great masters, Augustine and Aquinas, but also because denying newborn children the blessings of Heaven on a technicality began to seem like a chilly dogma indeed. Eventually Augustine’s position was disposed of by a ruling declaring it his own private opinion, not a binding church dogma. That still left Aquinas’ Limbo on the books; but, about 1985, Pope John Paul II appointed a commission of thirty theologians to come up with “a more coherent and illuminating” doctrine, and one member of that commission was Joseph Cardinal Ratzinger, the future Pope Benedict, who expressed his belief that “Limbo was never a defined truth of faith. Personally . . . I would abandon it, since it was only a theological hypothesis.” Now that he is Pope, he has indicated his support for a 1994 church document that said of children who die without baptism that “the church can only entrust them to the mercy of God,” which would allow innocent but unbaptized babes to have the solace of Heaven, and dismisses Limbo as unnecessary. The current anti-Limbo movement has come under attack by conservative churchmen who think that abolishing it will weaken the significance of baptism, but it is likely soon to win formal ratfication.

While the Catholic Church has wrestled with the Limbo idea for centuries (Protestants reject it as unsupported by Biblical authority), poets have felt free to use it in all sorts of interesting ways. Samuel Taylor Coleridge, for example, in his spooky poem “Limbo,” written about 1817, depicted it as a realm on the borderline between reality and non-reality, a sort of hyperspace whose inhabitants dwell in a perpetual waking nightmare of utter stasis:

“’Tis a strange place, this Limbo —not a Place,

Yet name it so; where Time & weary Space

Fettered from flight, with nightmare sense of fleeing,

Strive for their last crepuscular half-being. . . .”

It is, he said, a place “barren and soundless as the measuring sands,” that “frightens Ghosts as Ghosts here frighten men.” What he found so frightful was “the mere Horror of blank Naught-at-all.”

A nasty thought, yes. Coleridge’s Limbo is very different from Dante’s, that pleasant zone on the outskirts of Hell where virtuous pagans like Homer and Socrates whiled away their post-mortem centuries to the tunes of Orpheus’ lyre. Shakespeare, too, had a bleak view of it—in Henry VIII he uses “the Limbo of the Fathers” as a synonym for prison—and in Paradise Lost (1665) John Milton—no Catholic he—makes it a generic term, having Satan, wandering through the world, come upon “a limbo large and broad,” which Milton tells us is also known as “the Paradise of Fools”—the original fool’s paradise. This is a place where “the fruits of painful superstition and blind zeal” are to be found, “all the unaccomplished works of Nature’s hand,” a place full of “embryos and idiots,” and “hermits and friars . . . with all their trumpery” as well, and in a furiously anti-Catholic passage he describes the winds of Limbo tossing about “relics, beads, indulgences, dispenses, pardons, bulls,” and other Papist paraphernalia. Milton also lets us know that this ghastly Limbo is somewhere on Earth, “not in the neighboring Moon, as some have dreamed.” This is a direct reference to Ludovico Ariosto’s Orlando Furioso (1516) an epic poem that Milton knew well and had in part translated from the Italian. And here we come to what is, from our science fictional point of view, the most interesting Limbo of all—a lunar Limbo. In Orlando Furioso a knight named Astolfo travels to the Moon aboard a griffin and finds there not the barren orb that Neil Armstrong and Alan Shepard saw, but a vast realm stacked high with great heaps of things. Ariosto’s Limbo is “a place wherein is wonderfully stored whatever on our earth below we lose. Collected there are all things whatsoever, lost through time, chance, or our own folly here”: unfulfilled vows, broken treaties, unheeded prayers, desires that have led to nothing, useless fame, advice that has been ignored, and also such things as the discarded crowns of Persian and Assyrian kings, the promises of great men, the gifts presented by courtiers to princes, and many another artifact of human futility. A great pool of spilled porridge turns out to contain “charity, by sick men willed for distribution after they were dead.” A mound of twigs and limes: the witcheries of flirtatious women. And so on and so on, a wondrously corrosive stream of mockery, a harshly satirical lunar fantasy. (The seventeenth-century poet Alexander Pope, echoing Ariosto in The Rape of the Lock, added a few touches of his own to Limbo-on-the-Moon: “The smiles of harlots and the tears of heirs, Cages for gnats, and chains to yoke a flea.”)

In our own less poetic era Limbo seems to have acquired a new and appropriately twenty-first-century meaning. A bit of Googling around led me to the news that “Limbo is a new programming language, designed by Sean Dorward, Phil Winterbottom, and Rob Pike. Limbo borrows from, among other things, C (expression syntax and control flow), Pascal (declarations), Winterbottom’s Alef (abstract data types and channels), and Hoare’s CSP and Pike’s Newsqueak (processes.) Limbo is strongly typed, provides automatic garbage collection, supports only very restricted pointers, and compiles into machine-independent byte code for execution on a virtual machine.”

Automatic garbage collection! Newsqueak! Very restricted pointers! Machine-independent byte code! There’s poetry here too, my friends, though it’s poetry in a language I don’t speak. (“Limbo also provides Unicode strings, arrays of arbitrary types, lists of arbitrary types, tuples. . . .”) What are tuples, you may ask? “In effect, unnamed structures with unnamed members of arbitrary types.”

We are a long way here, I think, from Aquinas’ Limbo on the borders of Hell, or Dante’s seven-sided castle, or Ariosto’s lunar Limbo of wasted time, or Milton’s Paradise of Fools. As the church throws its Limbo overboard, the computer guys give us a new one. One way or another, it seems, we will always find a Limbo of some sort available close at hand as the centuries roll along.