A polite scratching at the door roused Celestia from the papers on her desk. "Come in," she called.
The door opened, and Twilight Sparkle entered. She noticed the mounds of paperwork on Celestia's desk, and flushed. "I'm sorry to bother you while you're busy, Pri— um, Celestia."
"It's quite alright, Twilight. I know full well that you wouldn't come here without reason. What is it?"
Twilight hesitated. Celestia waited, unperturbed and patient, until finally the words spilled from the little alicorn. "I don't know who else to turn to. Ever since I— since I became—" She set her mouth and gave an impatient flick of her wings. "I've been feeling more and more . . . lost? I don't know how to put it. The responsibility, the power, the magic—it's too much. I don't know what to do." The last word was heavier than its single syllable, and Twilight's face fell as she said it.
Celestia rose gracefully from her chair and came around the desk to Twilight. She smiled. "Walk with me, Twilight."
Twilight nodded and followed. They went in silence down out of the tower that housed Celestia's office, across courtyards and through hallways, each filled with castle staff who bowed or curtseyed as the princesses passed through.
At last, they fetched up in front of a discreet door, lightly ornamented and made of blonde wood. Celestia nodded at it. "After you."
Reflexively, Twilight balked, but the new instinct smoothly replaced the old, and she opened the door with barely a pause. She went through the door, and gasped.
Celestia followed, smiling. Twilight was gaping, agog at where she found herself. It was a narrow arcade, a straight walkway that faded into the distance, lined on both sides with slender, arching columns twined about with flowering vines. The ceiling was unworked stone, creamy white and groined between each set of arches. The midday sunlight reflected into the arcade from the nearby parts of the castle, illuminating everything with a clean, directionless light that cast no shadows.
The floor was a mosaic of tiny tiles, each hardly the size of a tooth. They formed a single straight line down the center of the arcade, with innumerable and multicolored lines and curves splitting off from it at seemingly random intervals. Each of the branches went to its side of the mosaic and ended.
Twilight finally shut her mouth and managed to speak. "Where are we?"
Celestia's smile was kind, as always, but more distant than Twilight was used to seeing. "This is my Walk. Come, and I will explain." They walked at a brisk pace through the arcade for a few minutes before she continued. "I laid each of these tiles myself. I work on the Walk a little each day. Sometimes, I lay a single tile. Sometimes, I lay many more."
Twilight could only think to ask one thing. "Why?"
"It is a form of meditation. I walk the Walk, and then I add to it. You have noticed the branches, of course?"
Twilight was put off-balance by the seeming non-sequitur. "I, yes?"
Celestia nodded. "The central line represents my life. It is the path I chose. The branches . . . they represent the paths not taken."
Twilight stared at the dozens of branches within easy sight, turning that over in her head. Before she could formulate a response, Celestia continued.
"Each branch has a story. Each one represents a decision that I made, consciously or unconsciously."
"I see," Twilight said, though she didn't.
"I became an alicorn in a time of great need. So great was Equestria's need for a leader, it shaped Luna and me into leaders."
Twilight was as confused as ever, but she was eager to hear more of Celestia's history. "Yes?" she asked, hoping to elicit more.
"I felt the same doubts that you are feeling now. The potential and the responsibility crushed me under and drove me to inaction."
Twilight blinked, then nodded thoughtfully.
"It took me some time to realize that the mechanism of my . . . advent could guide me along the right path. That is when I started creating the Walk. The central line is an unbroken chain of decisions for the betterment of Equestria. It gives me purpose. Stability. You understand, now, how important that can be."
"I see," said Twilight again, and this time she did. "So I should find my purpose."
Celestia smiled at her. "I think you already know it, my faithful student, but it is very like you not to know that you know."
Twilight stared quizzically at Celestia, pondering her words. She hardly noticed when they stepped off the end of the mosaic onto naked white stone. She was still mulling over Celestia's enigmatic smile when her ears pricked up at a sudden burst of laughter. Laughter Twilight recognized.
Twilight's mouth fell open as realization hit her like a kick between the eyes. Seeing it, Celestia's smile widened into a grin. Celestia turned off the Walk into a shady garden nook, and Twilight followed around one corner and a second before coming upon what Celestia had brought her to see.
"Twilight!" Five voices cried out in welcoming unison. Her five best friends were here, in the heart of Canterlot, seated around a picnic lunch spread out on the soft grass. Their smiling faces were as warm as the summer sun.
Celestia leaned close to whisper, "Set your course by friendship, Twilight Sparkle. Make your own straight line following their smiles."
Twilight could only nod. She heard her friends get up in surprise and come to embrace her as she started crying great heaving sobs of relief.