Three issues of physics are in play in the Netherworld. Firstly, the fires of hell need no fuel and do not consume what they burn—that would rather defeat the purpose, for it would have ended sinners’ torment too soon, which would not do. So hell’s designers saw to it that hellfire could burn but not damage, hurt but not destroy.

The second issue is one of time, which needed to be stretched in ways the scribes of hell tried very hard to grasp: hell does seem to teeter on the very edge of time. As early as twenty-five hundred years ago Hesiod thought that all beginnings and all ends contended just beyond hell’s gate, a very quantum idea. In the Buddhist called The Hell of the Sword-leaf-tree, sinners are condemned to climb and then descend a kilometer-long tree for as long as necessary, cutting themselves as they go, until the evil they have done in life is thoroughly scrubbed. Genshin, the Japanese monk who was a specialist in these things but who seems to have had only a hazy view of cosmological time, estimated at one point that ten trillion years would be about right.

The third issue seems more mundane, but is not: can hell ever fill up?


The matter of matter

Sometimes the fires of hell don’t seem to actually “burn” at all—that is, they burn but do not consume. Pope Innocent III asserted that “the fire of hell is not fed by wood nor kindled by wind, but was created unquenchable by God from the beginning of the world. Thus is it written, A fire that is not kindled shall devour him [the sinner]. The fire of hell, however, will always blaze and never give light, always burn and never consume, always afflict and never go out. For there is in hell the profoundest obscurity of darkness, an immense harshness of punishment, an eternity of misery. Bind his hands and feet and cast him into the exterior darkness: there shall be weeping and gnashing of teeth.” In this he was just echoing Saint Augustine, who pointed out, in his City of God, that if God is all-powerful, as he surely is, he is therefore perfectly capable of creating a body that can endure eternal torment—a great miracle, as Augustine declared, in obvious admiration.

But sometimes the fires of hell do actually consume, if only temporarily. Like the Prophet, Imam Kamil Mufti described how hellfire would burn off a sinner’s skin, which would then be renewed, to be burned off again, in endless cycles. “The Fire kindled by God will burn the skin of the people of hell. The skin is the largest organ of the body and the site of sensation where the pain of burning is felt. God will replace the burnt skin with a new one to be burnt again, and this will keep on repeating.” He quotes the Qur’an: “Indeed, those who disbelieve in Our verses—We will drive them into a Fire. Every time their skins are roasted through We will replace them with other skins so they may taste the punishment. Indeed, God is ever Exalted in Might and Wise.” The Prophet added a gloss: “Super-heated water will be poured onto their heads and will dissolve through it until it cuts up their innards, expelling them; until it comes out of their feet, and everything is melted. Then they will be restored as they were.”


How long before parole?

James Joyce, in A Portrait of the Artist as Young Man, recalled how as a teenager he had been burdened with the knowledge of souls in torment, while a mountain of sand a million miles high, a million miles wide, and a million miles deep, would diminish by the efforts of a little bird, which would carry away a single grain of sand every million years . . . after which, not a single instant of eternity would have ended. (This notion of the grains of sand and the little bird was cribbed directly from certain Buddhist texts, although they tended to use sesame seeds instead of sand). In this longish interim the souls had “ever to be eaten with flames, gnawed by vermin, goaded with burning spikes, never to be free from those pains; ever to have the conscience upbraid one, the memory enrage . . . ever to curse and revile the foul demons who gloat fiendishly over the misery of their dupes.”

Islam, whose hell is every bit as fierce as its Christian predecessor, nevertheless recognizes the awkwardness of a merciful god imposing unmerciful torture, and most Islamic scholars argue that evildoers will be punished in hell for an appropriate period and then cease to exist, so their suffering (which is graphically described in the Qur’an and therefore must happen) will not be eternal, but justly measured. Only one Quranic verse (22:47) actually mentions duration: it asserts that one day in the hereafter (in this context, hell) is the equivalent of a thousand years in life (“And they will bid thee hasten on the Doom, and Allah faileth not His promise, but lo! A day with Allah is as a thousand years of what ye reckon”).

Both the Hindu and the Buddhist traditions wrestle with the measurement of eternity, perhaps because in their view souls get multiple chances of redemption, not just the one shot envisioned by Christianity and Islam. They are often quite precise on how long a soul must wait.

For the Hindus, it would be hundreds of thousands, and perhaps millions, of years. For all practical purposes this sounds pretty eternal, but a soul must wait, after all, while it works its way through the deeds (or karma) of previous incarnations. The long-term goal is to seek release from the cycle of rebirths and attain union with the Ultimate Reality. This may take a long time, but it is not an eternity.

The Buddhists are more precise, sometimes hilariously so. In the Blister Hell, for example, which is a frozen plain surrounded by mountains and pounded by blizzards, sinners spend the amount of time it would take a little bird to empty a barrel of sesame seeds by taking a single seed every hundred years; and the time spent in each of the seven subsequent hells is twenty times the length spent in the one before it. Other descriptions escalate the quantity of sesame seeds to be removed at the one-a-century rate to 10,240 quarts; again, increasing this twenty-fold through the remaining hells, the final amount would be 510 billion quarts.

The hot hells are worse: in the first, the Reviving Hell, in which people attack each other with iron claws, sinners must stay for 1.62 Å~ 1012 years, or 1.62 trillion years, give or take an aeon (earlier for good behaviour). The final hell, Uninterrupted Hell, is much longer, 3.39 Å~ 1019, which comes out well into the quintillions of years.

Some of the Chinese Buddhist texts suggest that hell’s torments last a mere 432 million years, whereas a Japanese text from the tenth century maintains that the duration of the first hell is 9,125,000 years, and increases four-fold for each succeeding hell. The dour Irish priests who so terrified the young James Joyce would have nodded approvingly.

In the Western tradition, what arguments have been raised against this notion of eternal torment are not really physical at all, but philosophical: because humans have a finite lifespan they can commit only a finite number of sins worth punishing, and so isn’t eternity a little . . . disproportionate? Eighty years or so on earth, living according to confusing instructions and generally bad advice, draws an infinity in hell? Isn’t there, asked physicist Sean Carroll in an acerbic essay in Discover magazine, any notion of parole?

Jorge Luis Borges took up this theme in his La duración del Infierno. “No transgression can warrant an infinite punishment, for there is no such thing as an infinite transgression,” wrote Borges, thereby putting the case for heavenly sentence mitigation. Immanuel Kant took the opposite view, in an argument only an eminent philosopher could make with a straight face: since morality lies ultimately in a person’s disposition, and as disposition is concerned with the adoption of universal principles, or “maxims,” every human being is guilty of, in one sense, an infinite number of violations of the law, and so consequently an infinite punishment is not unjustified (this from Religion Within the Boundaries of Mere Reason).


How big is big enough?

Dante and others have agreed that, at the base of hell where Satan is kept, hell has frozen over. Yet the massive hellish rivers, Acheron and Cocytus, pour endlessly into the pit, never filling it up. And then there is this observation, from the Apocalypse of Paul:

I beheld and saw pits exceeding deep, and in them many souls together, and the depth of that place was as it were three thousand cubits; and I saw them groaning and weeping and saying: Have mercy on us, Lord. And no man had mercy on them. And I asked the angel and said: Who are these, Lord? And the angel answered and said unto me: These are they that trusted not in the Lord that they could have him for their helper. And I inquired and said: Lord, if these souls continue thus, thirty or forty generations being cast one upon another, if (unless) they be cast down yet deeper, I trow the pits would not contain them. And he said to me; The abyss hath no measure: for beneath it there followeth also that which is beneath: and so it is that if a strong man took a stone and cast it into an exceeding deep well and after many hours it reacheth the earth, so also is the abyss. For when the souls are cast therein, hardly after five hundred years do they come at the bottom.

Abyss upon abyss, down into the Deep . . .