There was only one teacher in the school, named Zhang Jinglin, and all subjects were taught by him alone.
Everyone thought the teacher was amazing, knowledgeable in everything. But Ren Xiaosu always had doubts. People always said that every trade has its specialty, and a person's energy is limited—so it wasn't possible for Teacher Zhang to be all-knowing, right?
Ren Xiaosu was different from most people. He liked to reflect when looking at problems. Later, after hearing Zhang teach, he learned this was called dialectical thinking.
Yan Liuyuan was sometimes puzzled—Ren Xiaosu often argued with Teacher Zhang's viewpoints, yet still ran over to the school whenever he had time to listen to his classes…
That afternoon, Ren Xiaosu even took Yan Liuyuan out to celebrate—not for anything else, but because from then on he could listen to the lessons from inside the courtyard.
Usually, squatting on top of the wall was too far; he couldn't hear clearly. Zhang Jinglin used to shut all doors and windows during class to keep outside noises from distracting the students.
But after discovering Ren Xiaosu listening in from outside, he began leaving one window open.
And now? He simply invited Ren Xiaosu into the courtyard.
Most parents in this chaotic world didn't send their children to school for knowledge, but so it would be easier for them to marry in the future—especially girls, who could marry into better families if they had been to school.
In these times, being literate and knowing three-digit arithmetic was already impressive.
Everyone was busy trying to survive. Who cared about knowledge when you could hardly find food?
Most parents had no long-term plans. In even this small town, there were rich and poor, and wherever there were people, there was comparison.
Yan Liuyuan watched as Ren Xiaosu bought a filter-tip cigarette from the general store. Old Wang proudly said his cigarettes definitely had no sketchy additives—they were very safe.
Twenty yuan each—rare things were expensive.
Yan Liuyuan asked in confusion, "Brother, what do you need a cigarette for?"
"Your teacher is letting me listen inside the courtyard. Even if I'm not paying tuition, I should show some courtesy," Ren Xiaosu smiled. "I know Mr. Zhang likes to smoke."
To Ren Xiaosu, if someone showed goodwill, he had to repay it.
The two brothers went to the back yard of the school during lunchtime. Teacher Zhang was eating stir-fried cabbage. Grinning, Ren Xiaosu offered the cigarette.
Zhang Jinglin didn't refuse. Instead, he told Yan Liuyuan, "Stand back. You're growing—smelling smoke is bad."
Ren Xiaosu said gratefully, "Thank you for letting me listen from the courtyard, sir."
"Hah." Zhang Jinglin lit the cigarette with the matches he used for cooking. He took a contented puff. "There aren't many students who still enjoy learning like you. If you want to listen, then listen. From now on, stand at the door—but you may not enter the classroom."
"Got it," Ren Xiaosu replied. "Sir, I have a question."
"Go ahead." The cigarette seemed to put Zhang in a rare, relaxed mood—he didn't mind whatever Ren asked.
"You said that before the Cataclysm, humanity had a lot of technology. Since humans weren't wiped out completely, why hasn't that technology resurfaced?"
Zhang glanced at him. "Right after the Cataclysm, no one even kept accurate count of how many years humanity was struggling. People barely managed to survive each day. Who had the energy for scholarship?"
"But surely some records must've been preserved? If we studied them, couldn't we restore civilization quickly?" Ren Xiaosu asked.
"It was a complete break," Zhang said regretfully. "If I give you full schematics to build an airplane right now, could you build one?"
"I've never learned any of that. Even with schematics, I'd still be starting from zero," Ren Xiaosu said.
"Exactly. Everyone is starting from zero."Zhang stared at his half-smoked cigarette, hesitating. He wanted to save the remaining half for later—but would that seem undignified in front of the boys?
Ren Xiaosu still felt something off. "But didn't anyone during those years persist through hardship to continue doing research?"
"No. They all starved to death," Zhang replied.
"So all that knowledge has really been lost?" Ren Xiaosu said unwillingly.
This time, Zhang looked at him seriously. "It still exists—but it's held in the hands of a very small group of people."
…
"Enough," Zhang stood up. "Stop asking about this. It's time for class."
Ren Xiaosu quickly asked one last question: "Sir, when were the walls of our barrier built? And why were they built?"
"After the Cataclysm, wild beasts roamed everywhere. They say long ago there was even an insect tide. Humans had no choice but to build high walls to block the danger," Zhang explained.
"But most beasts—even after evolving—don't actively attack humans," Ren Xiaosu said. "Monkeys are still herbivores, sparrows still eat grains. They don't try to eat people."
Barrier 113 was inside the human "safe circle." Most ferocious beasts were kept outside the "outer ring."
The higher the barrier's number, the more dangerous it was. The legendary Barrier 178 suffered casualties every year driving beasts away.
Barrier 113 was practically "the inner lands."
There were still dangers, like wolves, but nothing unmanageable. So why did such a large human settlement still need towering walls?
Zhang smiled. "As long as the wilderness is dangerous, refugees will rely on the barriers for survival. That means the barriers have a massive supply of cheap labor. Do you think the corporations behind the barriers lack the power to wipe out the beasts? Modern weapons are far stronger than you imagine. But why would they? The beasts don't threaten them."
Ren Xiaosu fell into deep thought. He was mature for his age, but there were many things he had never encountered—this was why he craved knowledge.
Zhang continued, "They will never tear down the walls. Why would the privileged class inside give up such a perfect natural class divide?"
Then he changed clothes. Ren Xiaosu asked, "Why change? Your clothes weren't dirty."
"The old ones smell like smoke," Zhang said, adjusting his collar. "It's bad for the students to smell it."
Yan Liuyuan was full of admiration, but Ren Xiaosu frowned. "Then why was it okay for me to smell it? You didn't tell me to stay away."
Zhang thought for a long moment. "Get lost."
At that moment, the palace in Ren Xiaosu's mind spoke again:"Mission: Desiring knowledge is never a bad thing. What you learn—teach it to others."
Ren Xiaosu froze. He had no idea what that mission even meant.
…
In the afternoon, the students were excited. A boy much older than them—Ren Xiaosu—was standing outside the classroom door, listening attentively. Many kept turning to look at him.
Zhang had to knock on the blackboard several times to quiet them. "Today we're having survival class."
This was the uniqueness of schools of this era—they taught not only academics, but survival.
But this particular class always gave Zhang a headache, because he'd barely been into the wilderness in his life. Born outside Barrier 113, now in his thirties, raised by his parents, then becoming a teacher—he really wasn't good at wilderness survival.
So he mostly read from old preserved documents.
He looked at the students. "Listen carefully. Don't think danger is far away. Your parents protect you now, but once you're adults, you must protect yourselves. Today we'll learn what to do if you encounter a wolf pack."
Survival class was the students' favorite—everything else was too boring for their age.
The classroom fell silent. Zhang looked at Ren Xiaosu by the door."You—tell us. What should you do when you encounter wolves in the wild?"
Ren Xiaosu thought and answered seriously:
"You should find a hillside with trees on all sides, because that way the feng shui is good for choosing your burial site."
Zhang Jinglin: "???"