In Zhou Junwu's later memories, that spring of the tenth year of the Jinghan era in the Wu Dynasty was quite unsettling. His burgeoning ambition for the study of natural philosophy suffered a heavy blow, and his research on gunpowder made little progress, even resulting in an explosion. His father, who usually paid little attention to him, confined him to the Prince's residence, forbidding him from going out. A group of tutors droned on all day about how his master's pursuit of natural philosophy was a lowly craftsman's skill, a base and frivolous art. Even his grandfather, the Prince Consort, didn't side with him this time. As for his sister, who was constantly being pressured to marry but harbored unrealistic fantasies, she was even less likely to be an ally.

The young prince, only thirteen years old, had found a direction he wanted to strive for, only to be met with a bucket of cold water from the world around him. The blow to him was quite significant.

It was truly exhausting, and he felt like he would never love again...

Of course, young Junwu's troubles didn't last too long. The impact of that spring on his entire life was immense. Towards the end of spring, his master returned from Hangzhou. Due to his confinement, he couldn't go out to visit him, but soon after, around mid-March, his master came to the Prince's residence. Although he didn't meet with the King for detailed discussions, thanks to his grandfather, the Prince Consort, he was temporarily allowed to go out, and his confinement was lifted.

At that time, scholars were quite particular about how they addressed their teachers. In the Prince's residence, those who taught Zhou Junwu were mostly great Confucian scholars from the Jiangning area, but Zhou Junwu still referred to them as "teachers." As for Ning Yi, after becoming fond of the study of natural philosophy, he called him "Master," and the distinction between the two was significant. Although Ning Yi was away from Jiangning for a long time, and the term wouldn't be used constantly, the differences were evident in subtle details.

The honored guests in the Prince's residence were all people of status and position. It was understandable that they were subordinate to Kang Xian, the Prince Consort, who had both status and profound knowledge, even if he hadn't achieved official recognition. However, Ning Yi was just a young man in his early twenties. Even if he was quick-witted and remarkably talented, and had earned the title of "First Talent of Jiangning," it was only in the minor art of poetry. No one believed that his actual knowledge surpassed theirs.

Because of this, Zhang Rui and Li Tong, two honored guests in the Prince's residence, had approached Ning Yi at the beginning of the previous year. That time, they happened to encounter assassins targeting Qin Siyuan, and Ning Yi's ruthlessness startled them, so they backed down. However, after Ning Yi left Jiangning, the little prince became increasingly fond of those artisan skills, and various resentments swelled among the honored guests in the Prince's residence. They repeatedly advised the little prince to turn back from the wrong path during lectures, urging him to study the way of the sages, but Zhou Junwu wouldn't listen.

Of course, the little prince's temperament was still good. He nodded obediently and accepted the teachings in front of his teachers, but then went back to doing his own thing. He only respected their status as teachers, not the individuals themselves. A group of teachers had also advised King Kang, but Zhou Yong had spent his life as a wealthy and idle king, and he knew that even if his son became like Kang Xian, it wouldn't mean much. If his knowledge were truly high, but he couldn't serve the country, he would become depressed. So he didn't interfere. If it hadn't been for the gunpowder incident, he would have been happy for his son to have some vulgar and boring hobbies, which was better than his daughter's lofty ambitions.

This time, when Ning Yi returned, due to some unusual movements on the part of Zhou Pei and Junwu, the honored guests in the Prince's residence also got wind of it. They discussed testing Ning Yi's knowledge of scriptures when he came to the door, so that the King and the little prince could see how unreliable this young man was. Of course, no one could truly look down on Ning Yi at this point, but even if Ning Yi was skilled in martial arts and had killed assassins on the street and returned from Hangzhou alive, personal courage was still a minor matter in the eyes of these scholars. A group of middle-aged and elderly scholars were confident that they could take turns defeating Ning Yi in poetry and scriptures without much difficulty.

They prepared for this, and when Zhou Junwu heard about it, he was quite looking forward to it. However, after accepting Zhou Pei's request, Ning Yi only called Junwu out through Kang Xian, and the group of honored guests didn't have a chance to issue their challenge. In the following days, the master and apprentice wandered around Jiangning City a few times, and Zhou Pei took the opportunity to go out and follow them. She had originally hoped that Ning Yi would persuade Junwu not to do those dangerous things and to strive for improvement, but Ning Yi led Junwu to wharves, workshops, and other places, telling him about waterwheels, the development of looms, and the ingenious ideas behind various machines, and so on. Ning Yi had told Junwu about these things in the past, but now he was speaking in more detail.

After wandering around like this for three days, when he sent the siblings back in the evening, Zhou Pei secretly ran out after entering the Prince's residence and pulled Ning Yi into the alley next to the Prince's residence, complaining, "You promised me that you would keep Junwu away from those dangerous things and help him strive for improvement, but now you're telling him about these things again..."

Ning Yi laughed, "Of course I have my reasons."

"But, you're only making Junwu like the study of natural philosophy even more. Maybe he'll start making gunpowder again in a few days. How can you do this? If Junwu..."

The young girl chattered anxiously, her face tense and her brows furrowed, saying a lot. Although her usual temperament was considered elegant and graceful, at this time, in terms of the image of a young girl, her head was a bit big, her chin was sharp, and her body was somewhat thin, like a little hen talking to herself desperately. Ning Yi tilted his head and looked at her for a long time, then flicked her forehead with his finger. The girl "whooshed" and froze, blinking her eyes and then falling silent.

"I have a way. Just watch, Princess. Don't question a professional."

Ning Yi waved his hand and turned to leave the alley. In fact, unlike Junwu's obedience, Zhou Pei had never had absolute faith in Ning Yi. Of course, this was only on the surface. The little princess was a very opinionated person. Even if she had already recognized Ning Yi's abilities in her heart, she would still say, ask, and question what she should at the first opportunity. Ning Yi actually appreciated this attitude. A leader shouldn't blindly follow their teacher or superiors, and the little princess did better in this regard than Junwu.

Of course, if Zhou Pei lost face and became unreasonable, Ning Yi would unceremoniously pat her head. But at that time, Zhou Pei was still a loli, and after a year, she had mostly developed the temperament of a young girl, so this action seemed a bit ambiguous. Zhou Pei blushed in the alley for a while, and finally stomped her feet and went back. In the past year, she had stopped her studies and was facing the pressure of marriage at home. Although she had been dragging it out, various pre-marital education had become her main daily task. At this time, being tapped on the head inevitably made her retreat to her room and ponder with her chin in her hands for a while.

The next day, it rained lightly. Ning Yi, Junwu, and Zhou Pei sat in Yi Lan Residence for a morning. They chose a window seat, brought ink and paper, and listened to the rain while Junwu explained some of his ideas and thoughts. Maids and servants sat around leisurely. Zhou Pei wore a veil very ladylike, nibbling on pastries under the veil, and rolling her eyes to peek at the movements of other places. The layout of Yi Lan Residence was actually similar to that of a tea restaurant in later generations. Each seat was separated by screens and flowers, and the view from any location wasn't wide, but it gave a kind of voyeuristic pleasure. When the sound of string and bamboo music came, it felt like a large group of people were touring a garden, combining elegance and vulgarity well.

"...Actually, there are several ways to conceive of flying into the sky. Starting from what we already have, we can divide it into three types: kites, firecrackers, and Kongming lanterns. We can draw them all..."

The things that Ning Yi and his little brother were writing and drawing next to them were naturally her greatest concern. They were talking about how to fly into the sky -- Zhou Pei was a little helpless about this. She knew that Junwu's greatest expectation after studying natural philosophy was to be able to fly into the sky one day, but it was enough for her little brother to fantasize like this. Today, Ning Yi, as his teacher, was seriously discussing it with him, and she felt it was a bit unreliable.

But the development of the situation was quite strange. It was raining outside, and in the faint singing in the restaurant, Mr. Ning actually drew quite a few things. He gradually structured the possibility of flying into the sky from the construction and principles... Flying? How could that be possible? They weren't immortals. But under Ning Yi's detailed and simple explanation, Zhou Pei looked at the graphics and vaguely felt that it might actually be possible to fly.

The most likely one was naturally a large Kongming lantern with a basket hanging from it. The other thing with two pairs of wings was more complex, but it evolved from a kite. Zhou Pei could even understand some of the basic principles. If large and small kites could fly into the sky, could this one... also be possible?

Such thoughts only flashed through her mind slightly. What frustrated her most was that after hearing these things, her little brother would probably become even more obsessed with that study of natural philosophy and want to become a craftsman. This Ning Liheng... Mr. Ning... didn't keep his word!

Then, she heard Ning Yi start to say other things to Junwu.

"...These past few days, I've taken you to see the loom, the hoist on the wharf, the waterwheel, and printing. These things have been developing. The loom now has more than 1,600 parts, and its efficiency has increased more than five times compared to 200 years ago, and more than dozens of times compared to the most primitive loom a thousand years ago. The development of the waterwheel is two to three times, and it is more durable. In the printing workshops, the woodblock carving has become better and better, and the craftsmen are more and more skilled. Movable type still has big problems now, but of course there is room for development. As long as we find a more durable material for movable type, when can we find it? If things continue like this, it should just be a matter of time..."

Zhou Pei pouted behind her veil, while Junwu nodded desperately. Ning Yi smiled: "But... in more than 200 years, do you know how many people have been doing this?"

He paused: "In the Jiangnan area, at least hundreds of thousands of people make a living by weaving. Over the past 200 years, how many generations have there been? Everyone relies on weaving to make a living. Being able to weave a little more means being able to earn more money. After the workshops rose up, large households like the Su family would at least support a few craftsmen to help improve the loom. Over the years, with so many people, the efficiency has increased fivefold. Some people only slightly improve a small part of it in their entire lives..."

When Junwu frowned in confusion, Ning Yi sighed: "Actually, the people who really research and improve the loom are all stupid people. The really smart people, as long as they have some connections, will all go to study. After all, all other occupations are lowly, only studying is noble. Anyone who has the opportunity to study, who would want to be a craftsman? But those who devote themselves to this line of work, even if they are stupid people, let's assume there are a thousand of them... Junwu, do you think you are more powerful than a thousand people alone?"

Junwu hesitated for a moment and shook his head.

"You were still young before, but now you are thirteen. Even if you can't start a family, you can start setting goals. I can really tell you about these things." Ning Yi placed a piece of paper with a picture of a hot air balloon in front of Zhou Junwu. "This is the simplest method we have set down now. There are several aspects of the problem that you need to solve: What kind of rope to use, what kind of fuel to use, how to most stably control the size of the fire. The fire must be big enough, but the fuel used to burn it can't be too heavy. The fabric used for the upper part of this hot air balloon must be able to seal and resist the heat of the fire, and it can't break. Once it breaks, even a small hole, everyone above will be dead. Any of these things require the assistance of other industries. Just to create this kind of easy-to-use fabric, you may have to be busy in the weaving industry for a lifetime. And the rope used above, you also know, even the way the hemp rope used on the hoists on the wharf is woven is related to the efficiency of the hoist. It's very particular... This hot air balloon can't even control the direction of flight. Can you do it alone in a lifetime?"

"Then... then what should I do..." Junwu's face was already wrinkled. Zhou Pei on the side was stunned for a long time, blinking at Ning Yi. She had already vaguely guessed what Ning Yi was going to say.

Ning Yi tilted his head, looking at the child in front of him with a somewhat bewitching smile: "You are still young. At first, you liked this study of natural philosophy because you thought it was interesting, but there is no such thing in the world as being able to do things happily and easily. Next, I want to tell you something that you can think about for a few years, because I may be going to the capital and won't have time to teach you these things anymore..."

"Your sister has always hoped that you will become a great man in the future, to establish a heart for the world and to create peace for all ages, but that's not possible. Although you are young, you actually know this, and King Kang understands it too, so he never cares about you. But you can do the study of natural philosophy in the future. The art of craftsmanship, there is no problem at all. You can have money, power, you can win over a large group of smart people, you can let them do all kinds of things with a purpose. As long as you can take overall control and grasp the direction, the time it takes to create these things can be shortened tenfold or a hundredfold. So first of all, you have to learn to be a smart prince, learn how to get more people to do the same things as you. You are very smart. If you are really interested, there are many people in the Prince's residence who can teach you this..."

When Ning Yi spoke of going to the capital, he had a sense of solemnity like entrusting an orphan. Almost at that time, little Junwu made his decision with surging emotions. And in the following months and even years, something similar to a sense of mission gradually accumulated in his heart along with one event after another: Some things, perhaps even Master can't do, but he can do them.

This is a story for later. At that time, the little princess Zhou Pei was even more impressed by his silver tongue. This day temporarily solved Zhou Junwu's matter. When he returned to the Su family in the afternoon, he heard Xing'er say that several Confucian scholars had come to visit in the morning. They were all well-known literati in Jiangning, and one of them was an honored guest in the Prince's residence. They invited Ning Yi to participate in a literary gathering two days later. This literary gathering was different from the poetry meetings where young people tried to show off their talents. All the participants were Confucian scholars with deep foundations, discussing poetry, essays, and current affairs. The group had waited for Ning Yi for half a morning. When they saw that he wasn't there, they left the invitation.

"I'm not going."

Ning Yi glanced at the invitation and, seeing that there were no words like "You must come or I'll kill your whole family," he threw it aside and forgot about it.