With the mesmerizing fair booming down in Ponyville and all of his chores marginally completed, Big Macintosh grappled with the idea of trekking into town. He took a seat next to Applejack on the living room couch and drew a deep breath.
“Watcha thinkin' about?” Applejack asked her visibly fatigued brother.
Mac reclined and folded his arms behind his head. “Chores are done. Thinkin' about goin' to town.”
“Oh yeah!” AJ exclaimed. “They got that fair from uh – oh, where's it from again?”
Mac shrugged. “Out of Equestria.”
“Yeah. Well, if your chores are done, go have fun. I'll let Granny know where ya are.”
“Thanks,” said Mac with a smile. “Want a souvenir?”
“Sure,” AJ replied. “Bring me somethin' fancy.”
Big Mac made his way into the kitchen and grabbed a soda out of the fridge. He chugged the icy nectar by the time he got to the front door. “See ya, AJ,” he called.
“Later,” she said from the couch.
Mac lumbered off the porch and onto the long road to Ponyville. A vague memory surfaced of his previous foray into town.
The streets of Ponyville were stuffed to the brim with energetic tunes and hypnotic lights. Mac swiveled his head back and forth to take in all the rich sights and sounds. Street vendors sat inside tiny stalls comprised of flowering fabrics and odd spherical lanterns. The music whirling through the streets was a dissonant amalgamation of instruments. It sounded to Mac like the main contenders were gongs and a series of twangy string instruments he hadn't heard before.
Crowds pulled this way and that, drawn to the alluring knick-knacks and the food stands billowing with steam. Pushing through the droves proved difficult even for a stallion of Mac's size. He stumbled through the bustling streets until a peculiar sight caught his eye. In the middle of a four-way intersection, an older pony donning orange garb sat high atop a wooden platform help up by slender poles. The guru-looking earth pony was well over ten feet off the ground. He sat with his legs crossed, peering through a pair of binoculars down the street at another identical pony – also sitting on a raised platform. The two did nothing except stare at each other through the binoculars.
Mac inspected the pony and his unusual seat. From high above, the monk called down to Big Mac.
“Hey!”
Mac looked up at him.
The pony rested the binoculars in his lap. “Is that me over there? Down the street?”
If he squinted, Mac could make out the other pony's appearance. His fur was a different color and he was wearing glasses.
“No,” he finally answered.
“What?” asked the monk, raising a hoof to his ear.
“That ain't you!” Mac shouted.
“Are you sure?”
“Yeah!”
The monk grumbled to himself. “Blast it. Can't hear a darn thing.” He swung his legs out and hopped down form the platform. Despite the clearly dangerous height of the drop, he landed with only a moderate stumble and several gasps from the passersby.
“There we go!” he said to himself. Once he relocated Big Mac, he walked over and beamed. “Can't hear a darn thing up there. Crowd's too noisy!”
“How'd ya get up there?” Mac asked, incredulous.
“Huh?” The monk looked confused.
“Up there,” Mac explained with a slight point toward the platform.
“Oh!” The monk walked past Big Mac toward the sidewalk. “I don't remember. Anyways, come over here.”
The two trotted between the chatty crowds and leaned up against the side of a building.
“Are you sure that wasn't me down the street?” asked the monk.
They looked back to the other platform, where the second pony had coincidentally descended as well.
“Eeyup,” Mac assured him.
“But, who am I?” questioned the monk. “Personhood is so dang hard to figure out.”
“What do ya mean?”
“Well,” the monk went on, “the root of the difficulty can be found in a question. Ask yourself: are you the same pony you were five years ago? Or as a foal?”
The answer appeared obvious to Big Mac. “Eeyup.”
“Don't be so sure,” scolded the monk. He sat down on the sidewalk and invited Mac to do the same. “First we have to understand the criteria for what constitutes personhood in the first place. Are we talking about physical bodies? Fur and skin and bones?”
“Sure,” said Mac.
“Fine. In that case, you've probably changed bodies at least twice already. Myself many more times than that.”
Mac shot him a look of disdain. “What?”
“Oh yeah!” The monk nodded. “It's true! Think about it. You shed your fur, new skin replaces the old, even the cells in your blood are constantly cycling through death and rebirth. In fact, every so many years, you have an entirely different collection of cells floating around your body than you did previously. They're yours, but they're entirely different. Can you truly call yourself the same as before?”
“Yeah,” asserted Mac. “My cells didn't up and change all at once. Besides, I look the same.”
The monk agreed. “True indeed. However, that's narrowing the definition of personhood to appearance. That won't accomplish much. Consider this paradox: if a well-worn ship has each board replaced individually over a series of months, is it the same ship when the last board is finally replaced? It looks the same. There's nothing noticeably different. Except that now all the pieces of the original ship have been discarded, so how do we identify the vessel? You can't logically conclude that it is or is not the same ship.”
Mac didn't fully agree. “I guess. That's the same as the body example.”
“You're right.” The monk crossed his legs and smoothed his robes. “Point is, there's no concrete answer. There is another side to the personhood coin though. Are you the same pony up here-” He pointed to his forehead. “-that you were five years ago or as a foal?”
“I'm a lot smarter,” Mac offered. “My brain probably changes and stuff. I dunno.”
“Let's use memories as the criteria now.” The monk produced his binoculars and looked through them at the crowds. “One theory states that person A is the same as person B if they possess the same set of identical memories. Can you see any holes in this assertion?”
Mac tapped his chin and thought for a second. “They could forget.”
“Exactly!” exclaimed the monk, still surveying the passing ponies. “That means if he conked his head and got amnesia, he logically wouldn't have existed up until that point – which is absurd. Additionally, I can't remember what happened in my dreamless sleep last night. Can you?”
Mac shook his head.
“That means that we didn't exist at that point and the ponies in our beds were not us. Logically ridiculous, right? And that's not even considering the inherent frailty of memories in the first place. The mind will edit memories when it doesn't have enough information to go on. It'll fill in gaps and manufacture events that didn't necessarily happen. So it's a very rickety assumption that A and B are the constitutionally identical on the basis of shared memories alone. Let me preempt the next theory with a small fictional anecdote. Let's say there was a colt who stole something from his neighbors. Later in life, he joins the army and becomes a mighty general. He still remembers the thievery as a child. Even later, when he's on his death bed, he remembers being a mighty general, but not the incident as a colt. So, this theory states that A and B are one and the same if they share a set of linked memories interwoven throughout points in their life.”
Mac finally sat down next to the monk and crossed his legs too. “That one sounds better.”
“Quite. Unfortunately there are still problems with this theory.” The monk took a moment to catch his breath and pool his thoughts. “If we could somehow copy your memories and transfer them to my own brain while simultaneously erasing yours, I would then believe that I am you, which is absurd. Even though my memories would be linked down to an earlier point in life and totally congruent, it would be false. Can you literally brain-jump from one body to the next and retain psychological continuity?”
“That's really confusing,” Mac said in exasperation.
“It's a question sans an answer,” added the monk. “Here's one last critical scenario. Picture a machine that can create an exact genetic duplicate of any creature. You step inside and while you're being cloned, you go unconscious for a brief moment. When you awaken, there are two of you and you both possess the same memories, emotions, intentions, et cetera. For the rest of your lives, you won't know who's the original big red pony and who's the replication. You'll think 'Who am I? Are my memories false? How can I be sure I did the things I remember doing?' It's a dangerous edge to dance on.”
Big Mac looked at his hooves with a focused expression. “I... am... myself.”
The monk threw back his head and laughed. “Of course you are. Was there ever any question about that? But you are normal. Who is somepony like, oh, say a split-brain patient? When the two hemispheres of the brain are separated, the resulting disparity makes for some interesting findings. Is there one consciousness or two? If there's no communication between the halves, what happens to the memories?”
“No idea,” answered Big Mac, puzzled.
“Just something to think about,” said the monk. “Listen, I should probably go find that pony who was staring at me. It's been great talking with you though. Good luck on figuring yourself out. Really. It's a journey we all have to embark upon at some point or another.”
“Thanks,” said Mac as the monk got to his hooves.
“No problem.” He trotted into the street. “Until we meet again. Or maybe we already did. Are you me? Are we each other?
Big Mac shook his head.
“Alright then,” said the monk. Without another word, he turned and penetrated the crowd.
Mac climbed up and resumed walking along his original path. Down the street, the other pony sat atop his platform with binoculars raised. When Mac looked behind himself, he noticed the monk sitting on his own platform, staring right back.
