The colors of Ponyville tonight are black and orange. Black, because everything is dark, and orange, because candlelight burns bright within each house.

Ponies are getting ready…ready for Nightmare Night.

Fly down the path leading from the Carousel Boutique, wreathed in glittering skulls with glinting violet eyes, toward the schoolhouse, its fields guarded by a host of grinning jack-o’-lanterns, their fiery eyes lit with a demonic blaze, along to the bowling alley where a lone skeleton, its fingers splints of shattered pins, menaces the entrance, and past the rows of houses, wreathed in cobweb and warded by ghouls, drop-down spiders hidden in trees and spooky monsters perched on fences, eyes glowing red. The town is ready, and now the ponies must prepare themselves for the trials ahead.

(And amidst all this darkness and flame are three pale lights hovering at the edge of the graveyard. The only word I can offer by way of explanation is yearning, and that is all we will say of them for now.)

Ah, excuse me. There is still one thing left to do, one thing to make Ponyville right on Nightmare Night. But even as I write, one pony is diligently attending to it.

Twilight Sparkle sets a small bowl piled high with sugar cubes by the corner of the door to her treehouse. Even though no pony remembers what it is for, they will remember not to disturb the bowl with sugar cubes piled high by a door on Nightmare Night. For it is true that a filly’s nightmares are the scars of their foremares.

Twilight Sparkle, her eyes hanging above the sugar cubes like the moon in the sky, looking down at the little cubes glittering faintly like distant stars in the reflected light of her eyes, makes a sound that isn’t quite a word, yet it yearns powerfully. It is the best she can do, and she turns in again, the door swinging closed behind her with an exaggerated creeeeeak, and a voice magically made moans “Welcome to your nightmare, little filly.”

You see, Twilight Sparkle understands two things about Nightmare Night in Ponyville:

1. It is about scary things.

2. Fillies come up to your door and knock and ask for candy.

So Twilight has used her magic to make a trap around the entrance to the treehouse. Any filly who blunders in will fall into a shallow pool of water. There are ladders for the fillies to climb up, but they are slippery and wobbly, like the disturbed expectations of the damp fillies. Only those who are truly determined will be able to escape the liquidity trap (they, and those who cry to their mothers).

Should the fillies still wish to venture within Twilight Sparkle’s domain, they will find themselves inside a treehouse. And a treehouse is…a tree, but made more suitable to the comfort of ponies. And trees, as every filly learns on Nightmare Night, are quite frightening things, with faces that follow you down the road and long jagged claws that arc out camouflaged against the dark sky and curve down sharply like a hook.

Old, big, libraries, late at night, empty of ponies, and so, so quiet but for an unrhythmic tap on the ground, a shuffle amongst the shelves…are really scary.

Get to know your local library, little fillies. You never know when you will be wanting something from it, not the least of which is to escape with your life….

Should the fillies pass through the terrible path of entrepreneurship and wish to brave further the treehouse and the twisted mind that made it, they will find a set of stairs that creaks and moans with every prime numbered step. Upstairs they will hear the heavy, leathery breathing that their nightmares embedded deep in their genes will understand is a dragon, and the threat of hot, instant nothing is near.

At the end of the long corridor is a bowl. It is full of treats—and not just any treat. Canterlot chocolates, ethereal concoctions of sugar, chocolate, and cream, some sticky with caramel and others shielded with a layer of nuts that do valiant but futile battle against the chomp of eager teeth. But no matter how far a filly may stick her hoof in, she never reaches the candy.

“You must pay the price,” a voice hisses, but when the filly turns around no pony is there. Trembling, she reaches for her bag of candy, ready to make a sacrifice at the alter of a Canterlot chocolate.

(Twilight doesn’t see why she shouldn’t benefit from the arrangement)

(Twilight has never dealt with parents before)

(Twilight is going to learn an important lesson about public choice theory)

Away from that horror, the horror of a choice, and back along the path until we reach the end where the orchards of Sweet Apple Acres blanket the hills. Ghosts whisper through the leaves rustling in the breeze, and fat apples hang down from the branches, those that survived the Scourge of Apple Bobbing and the Caramel Plague (or so it is remembered in the nightmares of apples). There we fade in through the glow of a window inside the house where Applejack is struggling into a rather odd costume. Behind her, Apple Bloom is doing much the same.

Look at these two sisters who strive together.

May you heed yourself, Twilight Sparkle! It is better to eat candy than to eat your heart out on Nightmare Night.

Applejack squeezed her head through the narrowing opening of the costume and wobbled unsteadily before finding her balance.

“Got it,” she said. “Okay, Apple Bloom, let’s take a gander.”

But when Applejack turned around, her jaw dropped.

“Apple Bloom? What kind of apple is that?”

“Tain’t no apple,” Apple Bloom said. “I’m Gum Disease.”

“What in tarnation are you thinking? We’re supposed to dress up as apples together.”

“Apples ain’t scary.”

“This ain’t about being scary, Apple Bloom. This is advertising.”

“Name one pony who don’t know about apples.”

“It’s about connecting with the customer base,” Applejack said. “Do I have to explain this again? We have to keep apples cool and fresh in ponies’ minds.”

“Well I’m Gum Disease,” Apple Bloom said. “After everypony gets cavities from eating too much candy they’ll be glad to satisfy their sweet tooth with an apple. Besides, I’m advertising our new service.”

“New service?”

“For the low, low price of three bits, ponies can have the once-in-a-lifetime guaranteed opportunity to brush a Cerberus’s teeth and gums. That’s a savings of five bits!”

“Five bits? Where’d that come from?”

“I just made it up.” Apple Bloom beamed. “I reckon it ain’t lying if there’s no truth to it in the first place.”

Applejack frowned.

“And, and, she’s all ready tonight,” Apple Bloom said quickly. “I got everything set up proper when all the fillies come by for their caramel apples and the Applelympics.”

Applejack grinned. Nightmare Night was going to be something special at Sweet Apple Acres this year. For one, no pony would need to stop to pee halfway through. (“It’ll be real good for the dirt,” Apple Bloom had said.) Fluttershy was doing the same thing she did every year, blindfolding the fillies and having them touch the different animals…uh, naturally something whatevers, and having the fillies guess what it was. It wasn’t any good, though, because Fluttershy always got too excited and blurted the answer. And as for Pinkie Pie…Applejack shuddered. She didn’t even want to know what that pony had gotten up to this year with all the forest’s resources at hoof.

At least she didn’t have to worry about any competition from Twilight. She was the sort of pony who handed out nuts and pamphlets on the dangers of eating too much sugar on Nightmare Night.

“Fine, you can be Gum Disease,” Applejack said. “Just be sure to tell your friends you ate too many oranges.”

“They won’t believe that. Can I go now?”

Applejack looked outside. “Fine, fine. I got to get going too. Let’s meet up at Rainbow Dash’s house later, okay?”

“Urgh, no way,” Apple Bloom said as she trotted out. “It’s all pranks. Who wants to hang out when every seat’ll zap ya and all the food is pretending to be worms? We’ll meet by Rarity’s place! I know you just want my candy….” Apple Bloom’s voice faded as she ran out and the door shut behind her.

Applejack shook her head. That pony was too stubborn for her own good. But she had her own friends to meet, and Applejack’s mind turned to the fun ahead.

So Applejack squeezed through the door and tottered down to one of the Sugarcube Corners where they planned to meet. There she saw Pinkie Pie, Rainbow Dash, Fluttershy, and Rarity.

“Howdy, y’all,” Applejack said, stumbling as she quickened her pace and rolling up to Rainbow Dash, who stopped her forward momentum and helped her up. “Thanks. What’re y’all dressed up as OH MY CELESTIA!”

“What’s wrong?” Rarity asked.

Applejack pointed. “Your, uh, uh….”

“Yes?”

“Rarity, your rump is showing.”

“And?” Rarity inspected herself. “Isn’t it always?”

“Fluttershy, that shirt is mighty sheer. Ain’t you afraid somepony is going to see something and think, well…you know….”

“Ooh, is this a guessing game? That I’m yellow? That my cutie mark is butterflies?” Fluttershy shut her eyes tight and squealed happily. “I’m so excited for Nightmare Night!”

“Applejack has a point,” Pinkie Pie said, lifting her mask to speak. “Ponies look a lot more revealing with clothes on. It’s kind of funny!” The mask slammed closed again.

“Funny?” Applejack said. “More like creepy if you ask me.”

A lavender flash marked Twilight Sparkle’s arrival.

“Hi, girls,” Twilight said.

“Hi,” they chorused.

“Twilight,” Applejack said, “have you seen the costumes these ponies are wearing? I swear every year it gets worse. Mares have no standards these days.”

Twilight looked at the group. “Fluttershy, are you a bunny?”

“You guessed!”

“Very nice. Rarity…Marelyn Monroe, am I wrong?”

“You are not.” Rarity twirled her skirt, eliciting a “Hey, now,” from Applejack.

“Guess what I am?” Rainbow Dash struck a pose in the air.

“Wonderbolts.” Twilight didn’t even look. “And….” She stared at Pinkie Pie.

“I’m the spirit of madness that haunts this dark town. Tee hee!”

“Got it. And, Applejack, you are…a lemon.”

“I am not!” Applejack said crossly while the ponies giggled. “I’m an apple—but not just any apple. I’m the sweetest, freshest, plumpest, roundest, reddest apple that you can only get at Sweet Apple Acres—“

“You can’t give her a lead like that or she’ll just keep going,” Rainbow Dash said. “And what are you?”

“What do you mean?” said Twilight.

“What did you dress up as?” Rarity said.

“Was I supposed to?”

“It’s traditional,” Fluttershy said. “Although I’m sure no pony will mind.”

“We don’t normally dress up in Canterlot,” Twilight said.

“What do you do?” Pinkie Pie asked. “Canterlot must have the awesomest parties!”

“Not…really. Nightmare Night is something for fillies in Canterlot. And I was always too busy studying even when I was that young.”

“Then your first official real Nightmare Night is here in Ponyville with your best friends!” Pinkie Pie cheered.

“First we gotta sort these costumes out,” Applejack said. “I can’t be seen in public with a couple of…of…you know, the sort of mare who goes about dressed like that! Why do mares dress like that anyway?”

“Oh, are we doing economics now?” Twilight didn’t wait for an answer. “Let’s take it for granted that a typical stallion and a typical mare have the same amount of total sex capital to spend on whatever they wish. But, we might observe that a typical stallion’s sex capital increases steadily with age after the initial endowment they receive during puberty. A mare’s sex capital, on the other hand, quickly peaks and then drops back down.”

“It’s terribly shallow,” Rarity sniffed.

“But it is, which is more important,” Twilight said. “And we can deduce some likely consequences. What this model suggests is that a young mare’s sexuality is very marketable, but as she ages this fades quickly. A stallion, meanwhile, will be awkward and not very desirable in his youth, but as he ages he will mature and attract mares much more easily. This is all a gross simplification, of course, but it has the ring of truth to it, doesn’t it?

“Now let’s suppose that there are, for whatever reason, a variety of norms and laws that discourage mares from spending their sex capital as they wish during its peak. This will not change the fact that mares want to spend their capital while it is available, and stallions want to buy! And so we might expect to see the development of certain focal points, or Schelling points, where the sex capital market can work relatively unhindered.”

“What’s a Schelling point?”

“A Schelling point is a point of a coordination ponies will be able to reach in the absence of communication. If you want a good time to give a pony a present, when will you do it?”

“Their birthday,” everypony said. “Unless Hearth’s Warming Day comes first.”

“Exactly,” Twilight said. “Everypony knows it, and everypony knows everypony knows it, so there’s no need to talk about it. If there are five ponies all in a line, all of which are the same height except for one who is much taller than the others, and Applejack and Rarity have to each guess which pony the other will select, and they can’t communicate, which one will they both pick?”

“The tall one,” Applejack said. Rarity nodded.

“Bingo,” Twilight said. “That’s a Schelling point. And so’s Nightmare Night. Just like it’s okay to give presents to a pony on their birthday, and it’s okay to knock on ponies’ doors and sing carols to them on Hearth’s Warming Day, it’s also okay to dress kind of slutty on Nightmare Night. It’s the sort of amazing coordination that can come about without any kind of explicit communication or central guidance that economists call spontaneous order. No pony had to plan to make Ponyville scary tonight. Ponies didn’t need to confirm to each other that they would all dress up and distribute candy. It just happens because everypony knows that everypony knows that everypony knows that this is what ponies do on Nightmare Night.”

“Except for you,” Rainbow Dash sniggered.

“The point is, it’s misleading to say that mares dress slutty on Nightmare Night,” Twilight continued, slightly louder. “Have you ever heard of the fundamental attribution error?”

Applejack sighed. “Nope.”

“When a pony is mad she tends to attribute that to her situation. ‘I’m mad because so-and-so was late and I had a bad night’s sleep and somepony was rude to me,’ she thinks. But when a pony sees some other pony, say, kicking a fencepost in frustration, she tends to think that that’s just an angry pony. That’s the fundamental attribution error, where ponies tend to explain the behaviors of others by their fundamental nature rather than their situation. Ponies often place too much emphasis on the internal and too little on the external when judging others.

“So are these mares slutty? Maybe, but another way of looking at it is that they’re rationally using a Schelling point to spend their sex capital during the relatively brief window they have available. It’s no surprise that there’s a huge jump in the ‘sluttiness’ of mares on such a night. Mares want to maximize the use of their assets.”

Applejack chuckled.

“Huh?” Twilight said.

“Oh, uh, I thought you were making a joke.

“I never joke about economics. Suppose there was a tree full of delicious red apples, but you could only pick it once a year. On that one night, you’d grab as many as you could. And if we assume mares are generally of sound mind and able to make decisions for themselves, what’s the harm? Some sound economic logic might tend to inure ponies to all the implicit sexism in this talk of sluttiness.”

“I ain’t sexist!“

“I know. I’m not making the fundamental attribution error!”

“All this talk about sluts is super interesting,” Rainbow Dash said, “but while we’re sitting here everypony else is getting a head start on the candy. We need to hurry if we want to get any of the good stuff.”

“Good point,” said Pinkie Pie, “but first we need a costume for Twilight. She’d look so weird around all the vampires and skeletons, and then everypony would do the factor arbitrage eradicator and think she’s weird, and that would be so sad.”

“Fundamental attribution—“

“No science! Now there is only fear!”

Laughing evilly, Pinkie Pie dragged Twilight inside the dark maw of the Sugarcube Corner, followed closely by the other ponies. She would emerge later with a costume of sorts, a balance of the influences of her five friends. And overhead the full moon shined bright on the night of terror and candy that lasted into the morning, and when Twilight returned home exhausted with a pulsing headache from too much sugar and a weird happiness in her chest that carried her up and into bed, she failed to notice that a small bowl by the door to the treehouse was empty.