Where's the Curvature, Twilight?
Fluttershy pushed in the door to Twilight’s tree home, instantly assaulted by the smell of old books. There was a gentle lighting in the main room of Golden Oaks, as the window perfectly caught the beautiful oranges and purples of the sunset.
Inside the library were two ponies and a dragon. The alicorn, Twilight Sparkle was reshelving her books for probably the third time that week. The other pony, the pegasus Rainbow Dash, was relaxing on a small army’s worth of pillows, reading a Daring Do book. The dragon was Spike. He was doing nothing interesting, per usual.
“Hey Flutters.” Rainbow Dash called from her little zone, peering over the top of her book for just a moment to recognize the new pony in the room.
This caught the attention of Twilight, who had been completely engrossed in her task. She turned around and smiled. “Hi Fluttershy. How are you?”
Fluttershy smiled back. “I’m great Twilight! I just came by to see if you have the new Compendium of Exotic Flora book I was looking for earlier.”
Twilight’s eyes lit up. “Oh I had it put somewhere around here.” After a brief moment of looking around, Twilight found it and levitated it over to Fluttershy, who happily grabbed it and slipped it into her saddlebags.
“It’s great!” Twilight gasped. “It has all these interesting plants from all around the world. Why, I didn’t even know about half of them.”
Fluttershy tittered. “I can’t wait! But it can’t be from around the world Twilight, the Earth is flat.”
For a few moments there was a very pregnant silence and Twilight struggled to accept what she heard was really true.
Twilight's eye twitched. "Fluttershy, what did you say?"
"Well everypony knows it, Twilight. The Earth is flat." Fluttershy replied.
"I'm sorry what?" Twilight replied icily, a bit more forceful than intended. Fluttershy shrunk back instinctively. "Fluttershy, the Earth is not flat. Ponethagoras discovered that almost 2,500 years ago."
"Well u-um... that was a long time ago, and a lot of thoughts from that time have turned out to be w-wrong..."
Twilight sighed and facehooved. "Okay Fluttershy, tell me why in Equestria you would get the crazy idea that the Earth is flat."
"U-um, okay. Well, there's the fact that we don't have any pictures from space... and Celestia controls the sun, which is probably a couple thousand feet from the atmosphere, and can just move in circles around the world. It'd probably be a lot easier than the theory that Princess Celestia is constantly moving the sun around an entire giant floating sphere, and that it's hundreds of thousands of miles out there. It's like... a spotlight."
"A spotlight." Twilight huffed. "You think the sun is like... a spotlight?"
Fluttershy looked around rapidly, meeting Rainbow’s gaze, who much to her chagrin, didn’t jump in to help her. Fluttershy looked back at Twilight meekly.
"Well I mean... Maybe that's not the best metaphor but..."
"Simile." Twilight corrected. "And Fluttershy, that's absurd! If the sun was that close to Earth it would scorch this planet dry!"
"W-we don't know that for sure."
"Fluttershy, really, the thing is-"
"Where's the curvature, Twilight?"
Twilight could swear she felt a neuron misfire in her brain.
"The... curvature?" She snorted.
Standing a little taller, Fluttershy continued. "Yes, the curvature. When I'm flying high in the sky I don't see a curve, which should mean the Earth is flat. Plus, the pegasus Dark Marble once took a closed bottle and flew absolutely straight for around 203 miles, and the glass level didn't change. It just stayed still the whole time. If the Earth is curved, it should lean to the side a bit, right?"
This time Twilight was sure a neuron misfired in her brain. "Fluttershy... do you know how gravity works?"
"Of course I do Twilight. I'm not stupid." Fluttershy replied indignantly.
"Alright, explain this to me then." Twilight smiled. "Gravity brings objects towards the center of the Earth, right? That's like... elementary school stuff."
"Of course." Fluttershy smiled back.
"Of course." Twilight quipped. "And I'm assuming the center of this 'flat Earth' idea you have is the North Pole, right?"
Fluttershy simply nodded.
"Great." Twilight nodded. "So in that case, when it rains, it should rain sideways."
"Yes, Twilight. But that proves nothing."
Twilight grit her teeth. "What do you mean, proves nothing?"
"Well..." Fluttershy tapped her chin with her hoof. "The Earth is really big. So while the rain would move a bit to the side, it wouldn't go straight sideways, Right? Besides, the rain does fall diagonally, so that just proved my point more."
Twilight's eye twitched again.
"I mean that is a decent argument, Twi." Rainbow Dash chuckled.
"Not helping, Rainbow!" Twilight hissed. "And that's because of wind currents! ...Alright Fluttershy, you know how constellations move?"
Fluttershy blinked in confusion. "I was not aware they did. Not everypony studies things like that like you do, Twilight."
Twilight rubbed her eyes with a hoof. "Alright, let's forget that one then. Fluttershy, if you go outside right now and fly up fifty feet, how far do you think you could see?"
Fluttershy paused for a moment to think about that. "I'd roughly say a couple miles?"
Twilight grinned, sure that she had Fluttershy now.
"Sounds about right to me. Now tell me, if you flew up another 200 feet, could you see farther?"
"Well, yes." Fluttershy raised her left eyebrow.
"So if the Earth was completely flat, then you could see the entire Earth. But since it's round you see more the higher you go!"
Fluttershy hummed softly. "Twilight, that makes no sense."
Twilight found her face stuck in frozen rictus. She genuinely had no idea to respond to that.
"Hey, maybe the Earth was round before Celestia discovered cake." Rainbow laughed.
Twilight turned to glare at Rainbow, who just laughed harder at her reaction.
"Spike!" Twilight called. Her draconic assistant ran to her side, parchment and quill already in his hand. "Pen a letter to Princess Celestia, we're gonna get this cleared up right now."
"Ready and waiting!" Spike simpered.
"Dear Princess Celestia," Twilight began. "Today an obdurate friend and I got into an argument about whether or not the Earth was flat. I combated her with facts and logic, and there was then an attempt to surreptitiously fire back at them with... conjecture!"
"I feel like I would be insulted if I understood some of those words." Fluttershy whispered to Rainbow Dash.
"I would appreciate it if either you or Princess Luna could come by or send a letter that could set my friend straight." Twilight finished. Spike sent the letter off in a little puff of green flame. Moments later there were two distinctive pops outside the library, immediately followed by Celestia swinging the door open with her magic. Princess Luna followed her into the library, them both wearing matching smiles.
Twilight paused. "You're both here? Right now?"
Celestia tittered. "I was in the middle of the most boring meeting ever. I told everyone else that the scroll sent news of another monster attack in Ponyville. I don't think anypony would have any problems believing that."
"And I was just bored." Luna chuckled. “Celestia grabbed me before coming down here.”
"Oh..." Twilight blinked. "Well, Princesses, could you please inform Fluttershy that the Earth is not flat?"
"The Earth is flat, Twilight." Celestia smirked.
"Yes, exactly Fluttershy! See, the princess herself said-" Twilight's eyes shot wide open and she turned to face Celestia. "WHAT?!"
"Only thing that's flatter is Luna." Celestia grinned.
"SISTER!"
Celestia started laughing wildly as Twilight's jaw comically dropped to the floor.
"Oh Twilight, I really expected you to know that. I'm so glad you have such good friends to steer you in the correct direction though." Celestia winked at Fluttershy, who beamed. "Now Luna, come. I must show you Sugarcube Corner. The cake there is to die for."
"I can't believe she actually fell for that!" Luna cackled madly. "I was sure she would call Fluttershy's bluff within a minute."
Celestia let out a low chuckle. "I've known Twilight far longer, Luna. I told you she'd react that way. Now if I'm not mistaken, you owe me a couple of bits for losing the bet."
Luna rolled her eyes and smiled, levitating a large pouch of bits to her sister. "She's gonna be so peeved when she figures out it was simply a ploy we involved her friend in. She's probably already tearing apart the library, trying to find enough information to write a research paper to prove us wrong."
Celestia's smile got smaller. "Yes, she will. I will go apologize to her later." Celestia let out a hearty chuckle. "But until then let us savor the sweet taste of victory."
