Every flap of her wings gave air to the fiery pain burning inside them. Rainbow Dash dipped and swooped under branches and around trees that burst out of the hazy snow-gloom with only a fraction of a second’s warnings.

A growing web of branches swiftly obscured her path to Twilight's bank. The hole was there but shrinking. Faster—she needed to go faster, and heaved her wings and felt something snap.

She spiraled toward the ground. One wing flapped and the other wouldn’t.

A skeleton-thin stallion was standing near her. He fished an hourglass out of his cloak and peered at the purple sand within.

“Butt out!” Rainbow Dash said when she saw him. “I don’t have time for you!”

The hole was nearly closed. She stabilized herself with one wing, reoriented, and sped off, cheeks pulled back too far by the wind for her to even scream at the pain. Faster…she needed to go faster….

“Ha!” said Rainbow Dash, dancing on the cloud. “I knew I was the fastest! Wow, a cutie mark! This is the best day ever! Hey, where’d Fluttershy go?”

They say that if you travel fast enough, you become light.

But they never say what color.

In fact, as Rainbow Dash knew, the color you become is all of them.

The air cracked louder than a cannon. A disc of rainbow blasted away from ground zero of the world’s second ever sonic rainboom.

Her wings weren’t hurting anymore. There was no muscle to tear. Rainbows aren’t made out of muscles.

The hole was nearly closed. It was too thin for a pony to fit through. A rainbow shot through the gap, and burst into a ragged Pegasus on the other side.

And a voice called after her, past her ears and directly into her head,

ARE WE STILL ON FOR TEA TOMORROW?

The daughter bank of Ponyville stuck out of the snow like the errant boot of a forgetful foal. A ring of trees surrounded it, or rather stayed away from it, a barren radius. A figure lay on the snow near a splash of red, and another stood over it, holding a shovel high.

Rainbow Dash tumbled and fell as strength failed her. Momentum propelled her forward, but her spiraling dive wouldn’t bring her anywhere near Twilight. At this speed, she needed just one more flap of her broken wings.

One flap that wouldn’t come.

The snow rushed up to meet her. A shovel was higher than she was.

But there was a hum in her flank. It vibrated through her whole body. For a moment, nothing hurt.

It was moment enough to flap her wings.

The air erupted around her with the force of a rainbow. She took off—

—at the wrong angle, and crashed and tumbled over the snow.

She rolled a stop by Twilight’s bleeding body, moaning in pain. Some kind of stone creature stood over them, a shovel in its mouth.

For a moment everything was still except flakes of falling snow and the colored light from a glowing cutie mark.

“Wish she had said where she was going,” Applejack said.

They walked, or limped, in Pinkie Pie’s case, in the direction Rainbow Dash had flown off. The snow was almost to their bellies now, and hidden thorns stabbed them from underneath.

“Where could she have gone?” Fluttershy whispered. She winced as she stepped on something spiky.

Rarity pointed.

“Possibly somewhere over that rainbow?”

Just snow, falling, and a shovel, not.

Twilight, bleeding from a shallow cut across her flank, slowly dragged herself on top of Rainbow Dash.

“If you were going to kill me, you would have,” she shivered. It hurt to talk, but she could now, once she had coughed the blood out of her throat and groaned for a while in the snow. As for her head, it had ascended beyond pain to a new realm of abuse, open and ready to accept anything.

There was a book nearly buried in the snow. The statue shifted its weight.

“Twilight!” Rainbow Dash said. The snow was thankfully numbing her wings. “What’s going on?”

“She’s deciding whether to kill us.”

“Oh.”

Snow fell down.

“Sorry,” Twilight added.

“Eh, it was bound to happen. At least I got to do something awesome before the end.”

The shovel wavered.

“Your cutie mark is glowing,” Twilight said politely.

“It is? Yes!”

Twilight bled a little.

“Okay, this is taking forever,” Rainbow Dash complained.

“Do you want it to happen fast?” Twilight said.

“I want everything to happen fast!”

“Have you made up your mind?” Twilight said to the statue.

The book lay in the snow, but they had been able to communicate long before then.

“It’s not easy, is it?”

Snow blew across the statue’s face.

“You’ve spent your whole life standing back from others,” said Twilight. “Always watching, never understanding. I understood. I understood, and that was my strength. I sacrificed what I loved for the sake of what I loved more, on the margin. I only failed once, and for that you condemned me?” Twilight struggled to sit better against Rainbow Dash. “But you never loved anything at all, did you?”

Something in the stone eyes flickered. The statue shifted, its face whipped around, shovel-blade carving through the air—

It stopped a fraction of an inch from Twilight’s neck.

“Or maybe you did.” Twilight closed her eyes. “I’m sorry I wasn’t more perceptive. To be fair, you were never the most expressive.” She opened them again. “Stop hiding behind that rock. Let me see you again.”

There was a momentary pause, and then a more definite one. The statue wasn’t just holding still, it was still, a piece of carved rock and nothing more.

Or perhaps not. It jerked suddenly, staggering upright. The statue turned and began walking in shuddery, grinding steps toward the discarded book. The shovel blade became a spear point without any obvious change, the black cloak faded into the form of proud wings. It picked up the book, shifted the spear from its mouth to its hoof, thrust it toward the sky, and was still.

“Oh, look, it’s the statue from the forest,” Rainbow Dash said. “I have no idea what’s going on.”

“I think my old friend became opportunity cost, destroyer of worlds,” Twilight said.

“You have the weirdest adventures.”

“You’re part of them!”

“Where is she now?”

It was a good question. And, Twilight realized, one with an obvious answer.

Just because she had lost sight of the mare didn’t mean she had gone.

In the same place as ever, watching…hopefully with a bit more fashion sense this time.

“Come close,” Twilight said to the empty air.

“Huh?” Rainbow Dash said. “I’m about as close as I can get.”

“Hold still,” Twilight said.

“I can’t move with you on me!”

“Try…to remember it.”

With the last of her strength, Twilight turned her head and pushed her lips out.

They met nothing.

She pressed them together once, and settled back.

The winds didn’t calm. The snow didn’t stop. The winter scene went on exactly as normal.

“Did it work?” Rainbow Dash said.

A smile spread over Twilight’s face like warm jam over toast.

“Yes. It works.”

By it she meant the world.

One of the truths about the world is if you are beat about the head and lose a lot of blood, you faint.

Twilight fainted.

Song.

Voices.

“What should we do?”

“It's a miracle that she's even alive.”

“She’s asleep.”

“Well?” Applejack said. “Wake her up.”

Something touched her shoulder and pushed her gently.

“Twilight?”

Twilight opened her eyes. Slowly her friends’ concerned faces faded into view. Twilight tried to sit up and found that she already was, propped up on a bed of snow. Her neck hurt. She felt weak but not light-headed. Then she saw the needle sticking out of her leg, and the clear tube connected to it, and she did feel light-headed.

“What’s going on?” she said. There was a line of stitching down her flank where the cut had been. Fluttershy was nearby, stowing things away in her medical box.

Applejack sat down in front of her, hat in her hoofs, hunched over like she was deep in thought. Her cutie mark was glowing. So were everypony else’s.

“Why are your cutie marks…?”

“I want to say goodbye.”

“What? Why?”

“You need blood. Fluttershy says we match.”

“I tested all of your blood types months ago after we beat Nightmare Moon,” Fluttershy explained. “It was just in case we had more adventures. I also checked for organ donation compatibility and other things. You were sleeping, it didn’t hurt a fly.”

Applejack tensed slightly as Fluttershy inserted the needle into her leg. “I like you, Twilight. And I reckon you’re the only one who can get Ponyville back to its regular self. But I ain’t going to give you my blood. I’m going to sell it to you.”

“But…you all said that selling things to your friends means you’re not friends,” Twilight said.

“Eeyup. Goodbye, like I said. But it ain’t up to me.”

“What? Why not?”

“There’s a spell on us,” Applejack said.

“What? How do you know?”

“Because I’m a witch,” Applejack said. “Also because I looked, and I noticed all of us but you and Rainbow Dash are acting real funny. That’s how I know. The witching is just knowing how I know.”[1]

[1] Whereupon Tiffany Aching burst through the portal and took pony form, clutching a cease-and-desist letter in her mouth and flanked by copyright lawyers on either side.

“You’ve all been acting perfectly rationally. More so than usual.”

“Don’t that strike you as strange? I came to you in need,” Applejack said, “and you helped me save my farm. You taught me how to choose among the things I love. The forest would still have me if I couldn’t. I learned my lesson, we all did, ‘cept Rainbow Dash. You taught me to listen to everypony, and to myself. But it makes a lot of noise. I ain’t sure the song of friendship has any place in that orchestra.”

Twilight’s jaw dropped. Even before she had awoken, the song had been faint beyond the edges of hearing, in that place where you heard your own voice speak back to you, the pony you listened to inside yourself. It was coming from their cutie marks, undamped by snow.

“So we reckoned,” Applejack squeezed her hat, “all that stuff about gifts and favors is old-fashioned. Money’s the way to, uh, allercate things. And once we started thinking like that, it seemed like friendship is just a way of deciding things that you don’t pay for. Should I pop over to Rarity’s for a visit? Wish Pinkie Pie a happy birthday? Send a pie over to Fluttershy? Used to be friendship said so, but that’s not as good as markets, so we’ll use them instead. That’s how we can really care for each other. That’s friendship.

“Only…thing is, it don’t seem very friendly. So busy haggling and exchanging that their ain’t no time for anything else. And I wondered if my own life hain’t taught me that what feels right, and what is right, ain’t always the same. Then the part of me that listens to me and talks back wondered if that wasn’t the greatest bit of self-fooling since Apple Bloom got her friends to whitewash that fence. Lucky me I got a me inside me who ain’t that stupid.”

“And I had a thought,” Fluttershy said. “Friends give me the things I can’t get myself. Like Applejack’s dependability, or Pinkie Pie’s cheer, or Rainbow Dash’s sincerity. If I can just buy them instead, then I don’t need friends.”

“And from the other side,” said Rarity, “if everything is for sale, then we have nothing to give.”

Pinkie Pie was covered in red marks and seemed tired. “We can’t keep going like this, but we’re afraid to stop. We don’t know what to do. And not knowing what to do, somehow it seemed like the one luxury money can’t buy.”

Twilight remembered the paralyzed fury of the scorned mare.

“For the record, I think they’re all crazy,” Rainbow Dash said.

“How are your wings?”

They were hidden in bandages, and Rainbow Dash was clearly trying to keep them still. “I’ll be flying soon enough.”

“No, you won’t,” Fluttershy said.

“Aw, Fluttershy!”

“It’s not up to me!”

“I’ll pay you!”

“It doesn’t work like that! Your wings need time to heal!”

“I’ll pay for that too!”

Fluttershy and Rainbow Dash groaned simultaneously.

“So anyway, we keep insisting on everypony paying for everything because of the magic spell,” Applejack said.

Twilight opened her mouth to say, “But that’s just how you feel, it’s not a magic spell,” and stopped.

Maybe the model needed a feel term.

Twilight closed her eyes. “I’m not sleeping, I’m thinking.”

She opened one eye. “Although if I start to snore, wake me up.”

She closed her eyes again and leaned back against the bed of snow.

At its core, economics was about opportunity cost. Opportunity cost was what you gave up to make the choice that you did. That meant economics was basically about alternatives.

Some ponies thought that ponies could afford irrational behavior if they were doing well, but if they risked going out of business, they would become more rational. They thought that the increased harm of a behavior would make ponies do less of it. There was sense to that view, but the only thing that could really change behavior was the presence of an alternative. Otherwise, no matter how harmful, say, an irrational pricing strategy was, ponies wouldn’t do anything different.

And once you started thinking about alternatives, there didn’t seem to be a reason to stop. An informal gift economy was one possibility. So was a hyper market-driven economy with no room for friendship. And no matter how much suffering that caused, as long as ponies lacked an alternative, they would keep on charging each other for breathing audibly.

When ponies went shopping, they were calculating and thoughtful about every decision—unless there was a cute saddlebag on sale, in which case all bets were off. But you didn’t calculate birthdays. You didn’t have to think at all. Send a card, buy them some variation of the same present you’ve always been getting them. And once you noticed that, it was everywhere. Greetings, goodbyes, and all the in-betweens were run on semi-automated programs.

Markets were calculating by their very nature, but most ponies lived their life according to patterns and norms. There had to be that barrier around money, that awkwardness about the subject of payment to a friend for services rendered.

But why should that be true?

It wasn’t an obvious question. But it was an alternative.

If she had taken away their old patterns, and now they were living on brute calculations second-by-second, then all she had to do was give them new ones.

She opened her eyes.

“Everypony, draw a circle around yourself in the snow. And don’t say I have to pay you, just want to.”

“Is this a magic circle?” Rarity asked.

“I tried to teach you all—except you, Rainbow Dash—that everything has an opportunity cost. There’s always a price, and there ain’t no such thing as a free lunch. That’s usually true. But not always. Sometimes you can get everything you want. It just takes a bit of magic. Or, to use the scientific term, technology.

“The circle around you is a kind of technology. Instead of bargaining over everything, we’re just going to say that everything in the magic circle is already bargained for. You don’t have to pay ponies to leave you be, or ask them to pay you if they want to bother you. Circle stuff is asymmetric and unfair; you are the boss of the circle and no pony can contravene you.”

“It’s going to be tricky when the snow melts,” Pinkie Pie said.

“You don’t have to literally have a circle around you. We’ll just say that everypony has a friendship zone around what is her and hers. Or property rights, if you don’t want to call everything friendship this and friendship that. I kind of do, though.”

“It’s all in our heads?” Applejack said. “Like a hat full of sky?”

Twilight wasn’t sure how to answer that, so she just plunged on. “There’s something weird about paying your friends for their time, isn’t it? Much better to be more generous with your time to them later. Or bring them a pie and never mention what they did for you. Or even just give them a big hug.

“And the question is, whyyyy? What’s the difference? What does money make so explicit? Why does that explicitness have to be awkward? Do we have to be so set in our ways? Who decided that, because it sure wasn’t me. Are there alternatives to the way we think and feel, and are those alternatives worth it?

“Who’s been thinking about friendship, anyway? Where are the scientists? How can we be sure that our friendship is optimal? It’s our task as economists—”

“We’re not economists,” Rarity said.

“—to make sure the way we practice friendship is the best it can be. That’s what it means to be best friends. I feel lightheaded.”

Fluttershy was instantly by her side, cradling her head.

“So yes, Applejack, I would like to pay you for your blood. As friends.”

Applejack broke out into the widest grin Twilight had ever seen on her. “And that’s okay?”

“Who decides? I don't see why we can't.”

“Fluttershy, will you do the honors?”

“Yes. Um…you don’t have to pay me though. If you don’t want to.” She flinched. “Is that all right to say?”

“Wow, the counter spell worked!” Rainbow Dash said.

“It’s not actually…sure, Rainbow Dash, just stay in that circle.”

Twilight closed her eyes as Fluttershy set to work. In the middle of Ponyville’s big freeze, among the most economically minded ponies in the world (however briefly), warm life flooded into her veins….

Such is the magic of friendship.

“I’m glad it was you,” Applejack said. Fluttershy had mercifully removed the needles and was swabbing some foul-smelling substance on everything, including them. “I couldn’t do it. Can’t do half of what my granny could. Got my cutie mark realizing that.”

“I got my cutie mark because I decided I had to have—aha, I couldn’t let you stop being my friend,” Rarity said, leaning forward. “You can do a lot more than you think.”

“That’s how I got my cutie mark,” Fluttershy said. “I decided I would decide the fate of every living thing.”

In a different season, crickets would have chirped.

“It didn’t sound creepy in my head,” Fluttershy said, her face the color of a banana-strawberry smoothie. “Actually, it was to do with your grandmother’s funeral, Applejack.”

“I got my cutie mark admitting how I felt about my parents dying and my sister casting me out,” Pinkie Pie said. “Did I never tell you all about that?”

“No!”

“Anyway, it happened when you girls came to my birthday party.”

“And I got my cutie mark being really fast,” Rainbow Dash said. “It all started when I had to stand up for Fluttershy….”

One by one they shared their cutie mark stories. Tears were shed, and a number of hugs exchanged.

“Hey!” Rainbow Dash said. “I just realized something. Your cutie marks are all related—to me! I was the one who found Applejack’s parents! I let Rarity try all her giant hats on me! I’m the one who showed Fluttershy how to catch toads, and I knocked over all of Pinkie Pie’s weird pony figures!”

“You’re right!” Rarity gasped. “Rainbow Dash connects us all.” When Rainbow Dash’s face was turned, Rarity hastened a wink to everypony.

But when she turned to Twilight, the lavender Unicorn’s face was awash with tears.

“Your cutie marks are connected,” Twilight said. “I listened to the stories, there is a thread stitching them together, even Rainbow Dash’s.”

“How did you get yours?”

Twilight smiled ruefully. “Getting my cutie mark was honestly one of the less interesting things that happened to me that day. I only remember a bitter smell and the overwhelming magic filling me up.”

She explained how she had come to meet Spike and be accepted into Princess Celestia’s personal student cohort.

“I, I’m sure it’s connected somehow,” Rarity said. “Possibly…because….”

“Dragons!” Fluttershy said. “They’re, um, really cute, and…so….”

“So you were like, I want more cute friends, and then you met us,” Rainbow Dash said desperately.

“Bitter how?” Applejack said.

Twilight tried to lift a hoof to wipe her face, but she just didn’t seem to have the strength. “You don’t have to try to cheer me up. I know I’m not part of…this, whatever this is. You’re all Bearers of the Elements of Equilibrium, connected through fate by your cutie marks, and friends since forever. And I’m…an awful friend.”

She began to sob. “I was afraid! I felt like if I gave the ticket to one of you, it was the same as taking it away from the rest of you. I didn’t know how to be a friend. I don’t have much practice. And because I didn’t want to hurt any of you, I hurt all of you.”

She told the story of her old mare-friend and what she thought had happened.

“I think I remember her,” Pinkie Pie said vaguely while the others stared.

“I should apologize too,” Applejack said. “Reckon we all should, though I’ll speak for myself. I should have seen the effect my greed was having on you. I let it blind me.” There was pain in her smile. “Sometimes I ain’t even as good as an apple.”

“None of us noticed,” Rarity said. “It’s not your fault.”

“What are you talking about?’ Rainbow Dash said. “I said she should just choose, didn’t I? Now I can’t go to the Grand Galloping Gala!”

“No pony said it was going to go to you,” Fluttershy said indignantly.

“Rainbow Dash, we bullied her,” Applejack said.

“What bullying? She should have just given the ticket to me!”

“You don’t learn, do you?”

“Learn what?”

Applejack was about to retort when Pinkie Pie stood up. She reached into her poofy hair and rummaged around. After a few squeaks, bangs, and a howl that could only belong to a surprised cat, she pulled out an inflated balloon.

She gave it to Twilight.

“The cutie mark doesn’t pick,” she said. “I do.”

Twilight had a hard time answering, not the least because she was holding a piece of string attached to a balloon in her mouth.

“Group hug time!” Pinkie Pie announced. As if on cue, her friends formed a circle and wrapped their legs around each other. Rainbow Dash screamed a little, and Applejack and Fluttershy both apologized and moved their hoofs under her wings.

Twilight felt she had neither the strength nor the right to join in, but Pinkie Pie’s leg seemed to extend to almost cartoonish proportions and pulled her into the circle. They squeezed her so hard the balloon popped. She sobbed at that, and the foalishness of it made her laugh so hard it hurt.

“You are not allowed to be outside of the hug,” Pinkie Pie told her, a smile stretching from ear to ear. “This is our magic circle, and you have to obey its rules.”

“Of course,” Twilight whispered, feeling very warm in the cold.

Who decided winter has to be miserable, anyway?

This is Third Winter, Twilight thought. It’s when you figure out how to fall in love with Second Winter.

By some unspoken agreement, the hug ended. Only Applejack’s strong hoofs kept Twilight from collapsing onto the snow, unable to move. She helped her lie down.

“I think we did it,” Twilight beamed. “I'm sure the forest will go away soon. We’re two for two on saving the world.”

What happened next was sudden and unexpected, like a denouement.

“Arguably,” said a dry, obnoxious voice behind them. “Arguably.”

Author's Notes:

Remember the scene where Buttercup pushes Westley down a hill?