Simultaneously traversing: the pinnacle of all realms

For the next few days, Xavier spent his time in a state of anxiety and tension preparing for the exam, and Ernie and the others could feel his sense of urgency.

On Wednesday evening, Xavier arrived at the principal's office as agreed. He took a deep breath and knocked on the door.

"Oh, come in quickly. What would you like to drink?"

Dumbledore's voice came from inside, clearly indicating that he had been waiting for a long time.

"Green tea, Professor, thank you."

After a few brief pleasantries, Dumbledore got straight to the point.

"What do you think?" Dumbledore picked up his teacup, looking at him through his half-moon spectacles.

What is the fundamental difference between alchemy and transfiguration?

This was Dumbledore's test; he wanted to see how Xavier understood it, which was important for later teaching.

Xavier opened his notebook and looked at the question he had written down in advance—this was exactly the first question.

He thought for a moment and then shared his previous understanding: "Transfiguration changes the external form of an object, while alchemy changes its internal essence."

Dumbledore nodded slightly, but did not say "yes" or "no".

He put down his teacup, picked up an ordinary stone from the table—probably just picked it up from the windowsill—and placed it in front of Xavier.

"That's a good starting point," he said, "but not quite accurate enough. Try it—transform it into bread."

Xavier drew his wand and tapped it lightly. The stone began to expand and change color, transforming in seconds into a round loaf of bread, golden brown and steaming. It looked perfectly edible.

"A wonderful silent transformation." Dumbledore didn't hold back his praise.

"Now," Dumbledore pushed the bread in front of him, "what will happen if you eat this?"

This is something Professor McGonagall emphasized in the very first lesson of first grade.

"This is dangerous because it will turn back into a stone in my stomach."

"Very good. What if you did the same thing using alchemy?"

Xavier put away his wand: "I don't know."

"But do you know what would happen theoretically?"

"It'll probably... turn out to be real bread. It'll be fine to eat it."

Dumbledore picked up his teacup, took a sip, and gave a gentle smile.

"Your answer is correct, that's the difference. Transfiguration only changes the 'external form' of an object—more precisely, how the object appears in your perception. Transfiguration doesn't change the fact that a stone 'is a stone,' it just temporarily makes a stone look, feel, and even taste like bread."

"What about alchemy?"

"Alchemy alters the relationship between objects and the world around them," Dumbledore said.

"True alchemy doesn't turn stone into bread—it involves the stone in the 'concept' that makes bread bread. In other words: Transfiguration changes the 'form,' while alchemy changes the 'nature.' You may not fully understand the difference between these two words right now, and that's okay—this is the first lesson in alchemy, and also the most difficult one. Many people spend many years without truly understanding it."

Xavier jotted down notes quickly in his notebook. He had a vague feeling that he had grasped something, but it was slippery, like a fish underwater—you could see its outline, but you couldn't pull it out.

Dumbledore watched him write, a hint of a smile flashing in his eyes.

"Professor Flitwick mentioned your question to me a few times. He said you asked, 'Can magic circulate within the body?'—this question itself carries an alchemical mindset. Most wizards only care about how magic is released outwards, but you care about how magic works inwards. That's rare."

Xavier looked up: "So, magic circulates within the body—is that alchemy?"

He came up with a term: human alchemy.

"Not really."

Dumbledore said, "But it leads to alchemy. At its core is not spells, not potion recipes, not cauldrons and fire—at its core is a way of looking at the world. When you start thinking about 'what things are like' rather than 'what things look like,' you're already on that path."

Xavier wrote in his notebook: Alchemy is a way of seeing the world. He underlined it twice.

"So, Transfiguration and Alchemy—are they from the same source?" he asked.

Dumbledore put down his teacup and tossed a cockroach-shaped chocolate into his mouth. Xavier even saw the cockroach's legs sticking out of Dumbledore's mouth.

"Of course they share the same origin, or rather, all magic originates from the same source, they just went in different directions." Dumbledore chewed on a candy.

"Transfiguration is about precision, clarity, and focused willpower—the clearer you know what you want to transform something into, the more successful your transfiguration will be. But alchemy is about understanding, resonance, and connection—the more you understand the essence of something, the more you understand its connection to the world around you, the deeper your alchemy will be. Transfiguration is about controlling external objects; alchemy is about understanding existence. Control can be strong, but understanding can be deep. The best wizards usually practice both."

Xavier thought of one person: "Nico Flamel—"

"Nico Flamel understood both of these to the fullest extent."

Dumbledore's expression softened. "He not only understands the nature of a stone, but also the nature of time, life, and death. That's why he was able to create the Philosopher's Stone—it's not simply a product of Transfiguration, nor is it simply a product of alchemy. It's the convergence of the two at the highest level."

A few seconds of silence fell over the office. Fox shifted his position on the perch, his feathers rustling softly.

"Let's stop here for now," said Dumbledore. "You already have a lot in your notebook. Next, we'll talk about the basic symbols of alchemy and their meanings. Before that—I suggest you read the first three chapters of 'The Fundamentals of Alchemy'."

Dumbledore made a book float to Xavier's side, and then continued,

"Mr. Xavier—in your notebook, I saw you drew an arrow between 'control' and 'understanding.' Have you considered that this arrow should be bidirectional?"

Xavier glanced at Dumbledore. The old man was holding a teacup and looking at him gently.

"I'll think about it," Xavier said.

It was already quite late when I came out of the principal's office.

Dumbledore didn't just teach Xavier alchemy; he also explained things like spells and transfiguration as much as possible. So it took longer than expected.

If Dumbledore hadn't chuckled and self-deprecatingly remarked that "old people need rest" and invited him out, Xavier wouldn't have realized how much time had passed.

Seeing that there was still some time before curfew, Xavier went straight to the library.

Inside the library, some upperclassmen were still preparing for their OWLs, most of whom were Ravenclaws.

Mrs. Pince raised an eyebrow when she saw the note in his hand with Dumbledore's signature, but she didn't ask any questions. She simply had him sign a borrowing registration form and then led him to the entrance of the restricted section.

"You can read the books on the list here, but you can't take them out of the library."

Mrs. Pince said, "I'll come to collect the books an hour before lights out. If you lose any of them—"

"That won't happen," Xavier said.

Mrs. Pince glanced at him, said nothing more, and simply stepped aside.

The restricted book section was much quieter than he had imagined.

The space between the bookshelves was narrow and dimly lit, with only a few rays of light filtering in from the main hall.

There was a distinctive smell of old books in the air—a mixture of paper, leather, and time. Hogwarts had such a vast collection of books that Xavier felt he wouldn't be able to read many of them even by graduation.

Xavier walked slowly along the bookshelf and found "The Theory and Application of the Unseen Stretch Charm"—a thick book with an open suitcase on the cover, and "Advanced Intermediate Transfiguration"—a book that was almost three times thicker than Professor McGonagall's textbook.

He sat down at a table in a corner of the restricted book section and opened to the first page of "The Theory and Application of the Seamless Stretch Spell." The spell was far more complex than any spell he had ever learned, and its casting principle involved a redefinition of space—the book used a metaphor that impressed him: it was like turning a bag inside out, but not the bag itself, but the space inside the bag.

He read it for a long time, sketching many spatial structures in his notebook, then crossing out most of them. The last one seemed to make some sense—he folded the sketch and tucked it into his notebook, deciding to ask about it when he had time.

When he left the library, he borrowed some more books from Mrs. Pince—all of which Dumbledore had mentioned.

This greatly saved Xavier time in his search, and Xavier suspected that Dumbledore might have read most of the books in the library.

When Ernie returned to the dorm, he came over and placed an egg tart on his bedside table.

This year he seems to have developed a liking for this again; even butter cookies have lost favor with him.

"Where did you go today? I didn't see you at the library again."

"I went to the principal's office. Then I spent a little while in the restricted book section."

Ernie's expression was as if he had choked on an egg tart.

"The forbidden book section? You? Wait—Dumbledore's office? What are you doing there again?"

"I asked a few questions," Xavier said.

"what?"

Ernie opened his mouth as if to ask more, but in the end he just shook his head.

"You're really strange. I avoid professors like the plague, yet you dare to go and ask the principal questions, Ethan."