The Poetry of Suffering in Buddhist Stories of Hells

Buddhist cosmology is fascinating. Its description of hell, for example, is extremely precise in its time-duration. Today we will measure the length, size, and the pain of hell.

Naraka is the hell in Buddhist cosmology. It differs from the hell of Christianity in two respects: firstly, beings are not sent to Naraka as the result of a divine judgment or punishment, but merely as a result of the evils (bad karmas) accumulated from previous lives; and secondly, the length of a being's stay in a Naraka is not eternal. After a creature's karma is used up, they will be reborn in one of the higher worlds.

Physically, Narakas are thought of as a series of cavernous layers which extend below Jambudvīpa (the ordinary human world) into the earth.

There are 8 hot narakas and 8 cold narakas.

The Cold Narakas

The cold Narakas are located at the extreme edges of the world, beyond the light of all celestial bodies, making them very cold.

 Arbuda (具皰), the "blister" Naraka

A dark, frozen plain surrounded by icy mountains and continually swept by blizzards. Inhabitants of this world arise fully grown, always naked and alone, while the cold raises blisters upon their bodies.

The length of life in this Naraka is said to be the time it would take to empty a barrel of sesame seeds if one only took out a single seed every hundred years.

Let's do a Fermi estimate.

Sesame seeds each occupies about a 1mm side cube, so has a volume of $1e-9\text{ m}^3$. A barrel has volume about $100 \text{ L} = 1e-1\text{ m}^3$. So it would contain $1e8$ sesame seeds, taking $1e10\text{ years}$ to empty.

Length of life: $1e10 \text{ years}$
Location: 1000 yojana = $1e4\text{ km}$ (beneath Jambudvīpa, the ordinary human world)
Size: A square of 10000 yojana = $1e5\text{ km}$.
Estimated population: Let's assume that each person gets a square of side length $1\text{ km}$, then it contains $1e10$ people.
Suffering: Covered in blisters. I don't know how much pain that is. Let's just call it one pain unit.

After this, each following level of cold Naraka has life 20 times as long as the previous one.

Nirarbuda (皰裂), the "burst blister" Naraka

Even colder than Arbuda. There, the blisters burst open, leaving the beings' bodies covered with frozen blood and pus.

Aṭaṭa (阿吒吒), the "atata" Naraka. 

There, beings shiver in the cold, their lips are frozen, making an aṭ-aṭ-aṭ sound with their tongues.

Hahava (頞哳吒), the "hahava" Naraka.

Basically the same, but with tongues frozen too, and the beings only make a ha-ha-ha sound.

Huhuva (虎虎婆), the "huhuva" Naraka.

You get the idea.

Utpala (青蓮花), the "blue lotus" Naraka.

The intense cold there makes the skin turn blue and splinter like the colour and petals of an utpala waterlily.

I like the imagery of blue lotus. It's beautiful and grotesque.

by Polkadot-Creeper

Padma (紅蓮花), the "red lotus" Naraka. 

Here, blizzards crack open frozen skin, leaving one raw and bloody, into eight rosy petals like a red lotus.

by familyof6

Mahāpadma (大紅蓮花), the "great red lotus" Naraka. 

The entire body cracks into pieces and the internal organs are exposed to the cold, also cracking. The whole body blossoms into a great red lotus with innumerable petals.

by colorlesscupcakes

The Hot Narakas

Still 1000 yajana underground, but not far away from the sunshine. Extremely hot.

Sañjīva (等活), the "reviving" Naraka.

Ground made of hot iron heated by an immense fire. Beings are attacked by each other and guards with fiery weapons As soon as the being experiences an unconsciousness like death, they are suddenly restored to full health and the attacks begin again. Other tortures experienced in this Naraka include: having molten metal dropped upon them, being sliced into pieces, and suffering from the heat of the iron ground.

Duration: according to Japanese Wikipedia, 1665312500000 years, or $1.67e12\text{ years}$.

In the hot Narakas, each level has a duration that's 9 times the previous one.

Kālasūtra (黒縄), the "black thread" Naraka

Note that the word sūtra appears. It's not a coincidence that sūtra both means "thread, rope" and "a text of wise aphorisms".

In addition to the suffering of the previous Naraka, black lines are drawn upon the body, which hell guards use as guides to cut the beings with fiery saws and sharp axes.

Saṃghāta (衆合), the "crushing" Naraka.

This level is surrounded by huge rocks that smash together and crush the beings to a bloody jelly. When the rocks move apart again, life is restored to the being and the process starts again.

Raurava (叫喚), the "screaming" Naraka.

Beings run wildly about, looking for refuge from the burning ground. When they find an apparent shelter, they are locked inside it as it blazes around them like a pot, while they scream inside.

Mahāraurava (大叫喚), the "great screaming" Naraka.

Same as the previous one, but with bigger pots, hotter grounds, and even more screaming.

Tapana (焦熱; 炎熱), the "heating" Naraka.

The ground is a steel plate heated red. Creatures are stabbed by iron skewers, and some are broken down into eyes, nose, mouth, hands and feet, each part burned with flames. Compared to the flame of this level, the flames of previous levels felt cold like snow. 

It's said that just a single bean-sized material from this level, if brought to earth, would burn everything on earth in a blink.

Pratāpana (大焦熱; 大炎熱), the "great heating" Naraka.

The pain here is equal to the sum of all the of the previous six levels, multiplied by 10. The flames here have a maximum height of $5000 \text{ km}$ and a width of $2000 \text{ km}$. The voice of a sinner's suffering sounds from hell even where it is $30000 \text{ km}$ away.

Avīci (阿鼻; 無間), the "uninterrupted" Naraka. 

 It is said that it will take 2000 years of free falling in order to reach this hell from earth. The suffering is all previous levels combined, and multiplied by 1000. Even the previous seven levels are a dreamlike happiness compared to this level.