Tang Dynasty: Starting at Xuanwu Gate, this prince is better off not being one.

"this……"

Wen Yu hesitated. From childhood to adulthood, no one had ever entrusted him with such an important matter. Now that Li Yu had suddenly asked him to handle such a big thing, in addition to being moved by the trust he had been given, he was also worried about whether he could live up to Li Yu's trust.

Seeing that he was still hesitant, Li Yu patted him on the shoulder again and said earnestly, "I know you are very passionate about physics, but it is absolutely impossible for you and me to study this subject to its fullest extent. It requires thousands upon thousands of people to study and explore it. Otherwise, this subject will be like those short-lived subjects in history, gradually disappearing into the long river of history over time."

After listening to Li Yu's words, Wen Yu gradually fell silent. After a long while, he finally asked, "Sir, even if I dedicate my entire life to it, will I never see the end of physics?"

Upon hearing this, Li Yu nodded silently.

Indeed, it is true. So many people throughout history have shed blood and sacrificed their lives for this field of study, researching it for centuries, yet they have never seen its end. Now, in this era where everyone believes the emperor is appointed by Heaven, any natural disaster is seen as divine retribution, and thunder and rain are attributed to the Dragon King and the God of Thunder and Goddess of Lightning. Trying to explore this field with Li Yu, a half-baked scholar who copied everything, and Wen Yu, whom he taught, will never yield any results…

Thinking of this, he said, "Physics, like the Hundred Schools of Thought, can even be said to incorporate the strengths of all schools. For example, the Mohist art of mechanics, the Daoist principles of the origin of heaven and earth and the mutual generation of existence and non-existence, the Zhuangzi's theory of the operation of heaven and earth, and the Yin-Yang school's theories of the Five Elements, solar terms, celestial phenomena, and mathematics. These can all be considered components of physics."

"Therefore, if we want to carry forward physics, we naturally need millions of people to explore and inherit it. Just like Confucianism, only by gathering all the new ideas of all Confucian scholars together, taking the essence and discarding the dross, can a discipline be carried forward."

"The pursuit of knowledge through investigation is a long and arduous task!"

"..."

.........

By the time Li Yu left the academy, it was already dark.

In the dim candlelight, Wen Yu looked at the book Li Yu had given her, lost in thought.

The words in the book were crooked and some were even illegible, but thanks to his grasp of physics, he was still able to read them fluently.

However, looking at the contents of the book, Wen Yu didn't know whether she should be shocked or how to react.

"If a thin bamboo tube is long enough, filling it with water can crush a wooden barrel?"

"No matter how big a piece of paper is, if you fold it in half, you can only fold it seven or eight times?"

"Furthermore, is the earth round? Is the sky infinite? Do we all live on one giant sphere? How is that possible?"

Wen Yu slammed her hand on the table and stood up abruptly.

Although he had come to believe Li Yu's words after spending time together, he found the gentleman's statements rather absurd!

Can people really live on a sphere? What about the people underneath? The author explains in his book that this is due to the existence of gravity. But what exactly is gravity?

He only now realized that his teacher was right. The pursuit of knowledge through investigation is indeed a long and arduous journey. It was virtually impossible for him to understand these things on his own.

As he pondered, his eyes gradually became lost in thought.

Looking at his own shadow swaying in the candlelight on the wall, he realized that he was much smaller than that shadow.

The shadow exists because of itself, but it becomes majestic with the help of the candlelight. Is this because of its own existence, or because of the existence of the candlelight?

"No, I cannot live without the candlelight!"

Thinking of this, he pushed open the door and went out.

Under the moonlight, Wen Yu stood in the courtyard, his shadow stretched long.

He glanced at his own shadow and slowly walked towards the backyard.

The academy was originally a temple that was temporarily converted, so in the backyard, there is a row of blue stone steps embedded in the back mountain.

This mountain is not very high, but standing on it, you can see the entire scenery of Chang'an.

Holding the torch, Wen Yu climbed the stone steps one by one. By the time he finally reached the top of the mountain, he was panting heavily and covered in sweat.

He stuck the torch in the ground and lay down sprawled out on an open space. A gust of wind blew by, carrying away some of his weariness.

With a bit of energy, Wen Yu scrambled to his feet.

Standing atop the mountain, he gazed into the distance, taking in the panoramic view of Chang'an.

Looking at the beautiful scenery before him, Wen Yu couldn't help but sigh, "If only I were half the height of this mountain..."

Only after he said it did he realize something was wrong. He was clearly taller than the mountain peak now!

Looking back at the steps he had taken to climb the mountain, and then back at the distant scenery, Wen Yu suddenly realized something.

"Could this be what you always mean by 'standing on the shoulders of giants'—that feeling?"

If you want to see further, is it enough to just climb higher? And if you want to see the end, do you have to climb high enough?

Where would he find a mountain that high to climb?

Thinking of this, Wen Yu looked at the steps behind him and suddenly realized something. If there were enough people pursuing "investigation of things to acquire knowledge," wouldn't his own ideas, when combined, allow him to see far enough ahead?

His gaze gradually hardened, becoming so resolute that it seemed capable of piercing the dark sky and touching the bright moon above...

.........

After several busy days, Li Yu finally handed over all the details.

After giving his instructions, he couldn't help but admire Li Er's thoughtfulness. Not only had he been given ten days, but he had also been assigned a personal bodyguard.

Looking at Chu He, who stood respectfully before him and Li Tai, Li Yu couldn't understand why Li Er would send Li Yuan's chief eunuch to protect them.

As if she could read Li Yu's mind, Chu He glanced in the direction of the palace, then turned to face Li Yu and said with a smile, "Your Highness, this old servant's trip to Lingnan with the two princes is at the behest of His Majesty and the Emperor Emeritus."

"I am deeply grateful for His Majesty's grace. Although I am old, I am still of some use. Therefore, His Majesty has assigned me to protect Your Highnesses and promised that when we return to Chang'an, I will be given the opportunity to live out my remaining years in peace."

Chu He spoke these words with a joyful expression, which immediately reminded Li Yu of the promise Li Er had made to him.

If nothing unexpected happens, this old eunuch, who has spent his entire life bowing in the palace, will be able to stand and speak to people for the rest of his life, as long as he can get through these few years...

.........