Zhu Xuan smiled slightly, looking very mysterious. “Well, we’re safe for now, so let’s talk about it for a moment.”

Su Xiaoyun and Shi Yitong looked at each other and they seemed interested. But I felt a little annoyed.

Seriously, why do you monsters always brag how erudite you are? To show how different you are compared to humans? To show that knowledge is power?

“There is a detailed commentary on the word ‘monster’ in the book ‘Kongtong Q&A.’ (TL note: the book was written during the Qing Dynasty, recording the conversation between a very famous Taoist master and an ordinary Taoist priest).” Zhu Xuan began his lecture. “A demon is a human being who lies and disguises himself so often that he loses his human nature. A fairy is the spirit of an inanimate object and also the spirit of a living creature besides human beings; a ghost is a lingering soul who refuses to move to the afterworld after a human dies. The world runs in a smooth and harmonious way, and abnormalities are rare. A god who strays from the right path becomes a fallen god. A human who is obsessed with immoral conduct is demonic, any belief or opinion that goes against the orthodox path is heresy.’ It is very clear here that a ‘demon’, a ‘monster’, a ‘fairy’, and a ‘ghost’ are different species, and the ancients had different definitions for them. But as time passed, after the Wei, Jin, Southern, and Northern Dynasties (220-589 AD), people no longer talked about them frequently. Because during this chaotic period, nothing was more important to the people than their own safety and the destiny of their countries. Therefore, the classification gradually became unclear. People began to call those things that they didn’t understand, ‘monsters’.”

“What do you think?” Zhu Xuan suddenly asked. “For example, how would you react if you saw a ghost that you had never seen before?”

We looked at each other.

“Well...” Su Xiaoyu hesitated and answered, “After all the things we’ve been through, I would probably think that it’s just another spirit.”

“So, when you turn on the light, you find out that it was me standing in front of you, what would you think then?”

Su Xiaoying was confused. She looked at me and Shi Yitong before saying, “Well.. of course, I would be relieved because it was you.”

“Would you think ‘Oh my god, it’s a monster’?” Zhu Xuan asked again.

Su Xiaoyu did not understand what he meant. “Of course I wouldn’t.”

“Why is that?” Zhu Xuan asked sharply, “You know that I’m actually a monster. But why would you think otherwise when seeing me? ”

“Of course it’s because——” Shi Yitong got anxious, but just before he said something, Zhu Xuan interjected.

“That is because you know and trust me, so you call me ‘Zhu Xuan’ instead of some vague name like ‘monster’, right?” Zhu Xuan smiled.

Shi Yitong nodded, half-understanding.

“Look, the same is true for the Beast Nian.” Zhu Xuan raised his head and looked around. There was nothing around us except endless darkness. “Because of the unknown, we fear; because of fear, we blame other creatures. Humans are accustomed to calling whatever they fear and don’t understand monsters, but in fact, there are various kinds of monsters, just like how Wen Jiubo and I are not the same kinds of monster.”

That surprised me. “What? Wen Jiubo and you are not the same kinds of monster? ”

This was the first time I heard of this.

“No. I’m a divine beast, and the nine-tailed fox is a demon monster. The little weasel that follows him is a fairy.” Zhu Xuan smiled. “So, to be more precise, the demons and monsters you have encountered so far are all different. But..”

Zhu Xuan suddenly changed his tone. “There are also monsters that are so special that they don’t belong to any of those types, like the beast Nian.”

“Different from any monsters?”

“Yeah, I think that theoretically, the beast Nian is not a monster at all.” Zhu Xuan lighted the surrounding with his phone. The black wind blades kept rotating to form an impenetrable wall.

“If it’s not a monster, then what is it?” Su Xiaoyun walked over and asked.

“Wen Jiubo once told me that the beast Nian is a creature living in a four-dimensional space,” I said hesitantly. “But I don’t understand what he meant by that.”

“Wen Jiubo is right, but it may be a little difficult for you to understand.” Zhu Xuan smiled. He crouched down, picked up a short wooden stick and began to draw something on the ground.

He first drew two points and then connected the two points with a straight line. He asked, “First of all, our world is three-dimensional, right? So let’s assume that there is a creature that lives exclusively in one-dimensional space. What do you think it will look like? ”

Su Xiaoyun, who had the best academic performance among us, began to study it carefully. She crouched down and said while pointing at the straight line drawn by Zhu Xuan, “A one-dimensional space is only made out of points. If there are creatures that live in one dimension, it must be a point. There is no spatial concept such as area or volume in a one-dimensional space, only linear information such as points.”

“Bingo,” Zhu Xuan said. He was obviously pleased with her answer. “One-dimensional space is isolated. If there are creatures in a one-dimensional space, then they can only perceive points on the line, but they can’t see the line. But, if ——”

Zhu Xuan added a rectangular plane on the line he just drew.

“But if we have a two-dimensional space?”

“Then you can see the points and the lines,” Su Xiaoyun answered immediately.

Zhu Xuan nodded. “But there are still many limitations for two-dimensional creatures. Although we have a geometric area, there is no volume, and creatures in two-dimensional space can’t see the area. So, how can we make them realize the existence of the area?”

Now I began to understand what Zhu Xuan said. I took the branch from his hand and drew a cube.

“Of course, we need to turn it into a three-dimensional space. The three-dimensional space has both area and volume. Similarly, the living creatures in the three-dimensional space—that is, the world we live in, can see the two-dimensional space.”

Shi Yitong got impatient and stood up. “Well, Zhu Xuan, I learned everything you’ve been talking about in high-school. Even a low-score student like me knows what dimensions are. Why did you waste all this time to talk about this? Aren’t we supposed to find Wen Jiubo and Xu Yingchen and leave this place as soon as possible? ”

“Don’t worry. Didn’t I just say that we are safe for now? Moreover, if you want to solve problems once and for all, you must first figure out the fundamental issues.” Zhu Xuan smiled mysteriously. “And the question I’m going to ask is not easy to answer. That is——what we should do to see the full picture of the three-dimensional world?”