Zhang Pingzi was Zhang Heng. Across two hundred years of time and space, Guo Pu had unilaterally apprenticed himself to Zhang Heng. Zhang Heng believed heaven and earth were like an egg—heaven like an eggshell, earth like the yolk—so heaven and earth were a large sphere containing a small sphere.
This was a minor disagreement within a major school of thought—both believed heaven and earth were spherical, but they defined the details of that sphericity differently.
Zhao Hanzhang felt they could completely seek common ground while reserving differences.
“…On this point, I agree with Tinghan. But whether it’s double spheres or a single sphere, we can set aside the dispute for now. After all, they’re both spheres—why not calculate the timing of the solar eclipse first?”
Guo Pu said firmly, “No. This is an academic debate—how can we be careless? Unless he admits to the double-sphere theory, I won’t calculate this with him.”
Zhao Cheng interjected, “How could the Earth star be spherical? If it were spherical, how could we stand on it? The Earth star should be round heaven and square earth.”
This represented yet another school of thought. Guo Pu vehemently objected. “You can’t assume the earth is flat just because your eyes see the ground as flat. This argument is inferior even to Fu Tinghan’s.”
Zhao Cheng countered, “You say the earth is round—what evidence do you have? Even Zhang Heng couldn’t produce evidence.”
Guo Pu was stumped.
Yuan Li on the side nodded slightly.
Zhao Hanzhang glared at him. “What are you nodding at? Do you even know who Zhang Heng is?”
Yuan Li truly didn’t know, but he understood what they were saying. He could comprehend the square-earth-round-heaven concept but couldn’t understand the round-earth-round-heaven idea.
However, he couldn’t openly oppose Zhao Hanzhang, so he decided to silently agree with Zhao Cheng in his heart.
Guo Pu frowned and countered Zhao Cheng’s argument: “If heaven is round and earth is square, there will always be parts the round cannot cover. Wouldn’t the four corners be exposed outside? When people at those four corners look up, if there’s no heaven, what do they see?”
Zhao Cheng replied, “Heaven is large and earth is small.”
Zhao Cheng then used Guo Pu’s viewpoint to refute Zhao Hanzhang: “If the Earth star is a single sphere, what is this heaven we see when we look up? Wouldn’t all things be exposed to the universe?”
Guo Pu became distressed and turned to Zhao Hanzhang. “I have no physical evidence to prove round heaven and round earth. If you and Fu Tinghan have a way to prove it to the world and convince stubborn people like Zhao Cheng, then I can temporarily set aside our differences and, as you said, seek common ground while reserving differences.”
Zhao Hanzhang opened her mouth and realized that even with her silver tongue, she would have difficulty making Zhao Cheng and the others accept her viewpoint at this moment.
Zhao Hanzhang suddenly thought of a problem. Fu Tinghan’s mind was filled with so much natural science knowledge, and she could accept it, but what about others?
If he couldn’t gain acceptance from mainstream intellectuals, and that natural knowledge couldn’t be transmitted, couldn’t be verified, what use was it even if they knew it?
Only when knowledge gained acceptance could it be passed down!
Zhao Hanzhang became serious and nodded solemnly to Guo Pu. “Tinghan and I will find a way to verify that the Earth star is spherical, and that we live on this sphere—there is only one sphere!”
Guo Pu couldn’t help himself and again disputed with her over single versus double spheres, pointing a finger upward. “Then what do you say that is? We’re already on a sphere, yet this heaven is also spherical, currently covering us inside it.”
Zhao Hanzhang countered, “If there’s an eggshell-like round shell above our heads, how do we see through this shell to the stars, sun, and moon in the universe?”
Guo Pu fell silent.
Zhao Cheng interjected appropriately, “The earth is square and heaven is round. As for why we can see the stars, sun, and moon through heaven, I also don’t know.”
Yuan Li looked at one person, then another, and couldn’t help saying, “The stars are in the sky.”
The three said in unison, “You be quiet!”
Yuan Li felt somewhat wronged—he didn’t think he was mistaken. The stars were in the sky.
Guo Pu was too lazy to explain to this commoner.
Of course stars weren’t in the sky—they were beyond heaven.
Or rather, it was Zhang Heng who said, “The expression of space has no limit, the extremity of time has no end.”
Guo Pu’s astronomical knowledge was inherited from Zhang Heng’s theories. Unlike ordinary diviners, Guo Pu came from an aristocratic family and had enjoyed superior learning environments and abundant learning resources since childhood.
Zhao Cheng knew less in this area, but he had basic astronomical knowledge. The concept that the universe was infinite and limitless didn’t originate with Zhang Heng but had existed since ancient times—Zhang Heng had merely simplified and more clearly articulated it.
He was also a teacher, so while Guo Pu was pondering the problem Zhao Hanzhang had posed, Zhao Cheng explained to Yuan Li: “Space has four directions—above, below, and all around—and these four directions have no ultimate boundary. Time has past and present extending indefinitely, and past and present have no limit.”
“Heaven has its limits, so stars are not in the sky but beyond heaven. The moon and sun are the same.” Zhao Cheng continued, “Precisely because the moon and sun are both beyond heaven, solar and lunar eclipses occur.”
Yuan Li’s eyes were confused—he had listened but didn’t understand.
Guo Pu had already recovered and, glancing at him, said, “Stop teaching him. Most people in this world are stupid—not everyone can comprehend celestial principles.”
Yuan Li: …
If it were any other minister, he would definitely be angry, but Guo Pu… well, he truly was incompetent in this area.
“So you agree with Fu Tinghan that this so-called heaven is a layer of gas?”
Zhao Hanzhang nodded. “Correct!”
Guo Pu’s brow furrowed tightly. After a long while, he shook his head. “No, I still don’t believe it. However, this matter can be temporarily shelved. Right now, we should focus on proving that heaven is spherical. I don’t want to argue with people about whether earth is square or round every time I report on calendar progress.”
Zhao Hanzhang thought for a moment. “Then there are only two methods to resolve this.”
Guo Pu’s eyes brightened. “What methods?”
“First is to find a ship and sail eastward across the ocean, continuing east to see if we can return to where we started.”
Guo Pu said, “…Tell me the second one.”
“The second is observation,” Zhao Hanzhang smiled. “I think Tinghan must have also told you about latitude and longitude. If everyone doesn’t believe it, then observe. Measure the height of the North Star from various locations and see the angular differences at different locations—you’ll discover latitude. Since you can calculate solar eclipses, you can certainly calculate lunar eclipses too. When solar and lunar eclipses occur, calculate the time differences between east and west locations, and you’ll discover longitude.”
Guo Pu’s mouth fell open. This was something Fu Tinghan hadn’t had time to tell him. He looked at Zhao Hanzhang suspiciously. “You and Tinghan have measured and calculated this?”
She had only lived this many years—before age fourteen in Luoyang, and after fourteen always surrounded by people. How could she deceive him?
Zhao Hanzhang didn’t hesitate for even a moment and said directly, “I learned it in a dream. Knowledge transmitted through dreams—Heaven’s mandate revealed to me.”
If it were anyone else, they definitely wouldn’t believe it—for instance, Zhao Cheng and Yuan Li both instinctively questioned the truthfulness of her words.
But Guo Pu immediately believed.
He murmured, “So that’s it. No wonder he always knows things I don’t, and whatever you say, he understands. Whatever he says, you can also comprehend. It turns out it was transmitted through dreams…”
Guo Pu’s eyes grew brighter and brighter. “Hmph, he tried to hide it from me. No matter how I questioned him, he refused to say.”
Guo Pu praised Zhao Hanzhang: “The General is still sincere in dealing with people.”
Zhao Hanzhang nodded, accepting his praise.
Zhao Cheng and Yuan Li: …
What to do—they felt a bit restless. Shouldn’t it be that Fu Tinghan was honest and didn’t speak falsehoods, while My Lady…
Bah bah bah! Yuan Li suppressed his thoughts and dared not reveal them.
Zhao Hanzhang told Guo Pu, “Set aside the single-sphere versus double-sphere dispute for now. Let’s first address the round-earth versus square-earth disagreement. When Tinghan returns from the Yellow River, I’ll have him make observation tools for you. The immediate priority is calculating the specific timing of the solar eclipse.”
Only then did Guo Pu set aside his bias and solemnly agree.
Fu Tinghan and Zhao Hanzhang believed that a solar eclipse was just that—a natural phenomenon. But Zhao Hanzhang knew ancient people wouldn’t think that way.
For instance, Guo Pu, this ancient person.
At this moment, he looked seriously at Zhao Hanzhang and said, “The sun represents the ruler. When the sun is obscured, it means the emperor is no longer suitable to rule. Since even someone of my meager abilities can calculate indications of this, it’s already beyond remedy. Therefore, we can only ask His Majesty to issue an edict of self-blame or abdicate to a worthy successor.”
Zhao Hanzhang lowered her eyes in thought for a moment, then said gravely, “Let’s not mention this matter for now. First calculate the specific timing.”
She would also go back and think about whether she could recall this event from her memories.
She needed to prepare in advance to prevent any accidents.
The Celestial Dog devouring the sun didn’t have just one interpretation of the emperor’s失德 loss of virtue—there was another: treacherous ministers in power.
Though her reputation among the people was good, no matter how good, there would still be opposition. So she needed to prepare in advance.
Zhao Hanzhang instructed Zhao Cheng and Yuan Li, “This matter is confidential and must not be spread.”
Zhao Cheng and Yuan Li bowed and agreed.
Zhao Hanzhang then looked at Guo Pu, feeling a slight headache.
Zhao Cheng and Yuan Li were famously tight-lipped—otherwise one couldn’t be a good teacher and the other couldn’t become an intelligence chief. But Guo Pu…
This was a contradictory entity.
To say his mouth wasn’t tight—ordinary people couldn’t extract a word from him. To say his mouth was tight—after becoming good friends with Fu Tinghan, during rest and leisure time, Fu Tinghan could always hear various gossip from him.
Fu Tinghan would then tell her, and it could be said the scope was vast and private—truly unheard of.
One of the most shocking to her worldview was that in his early travels, Guo Pu had once told a fortune for a wealthy landlord. The landlord was very grateful and thought Guo Pu’s genes were especially good, so he invited him to sleep with his wife and leave a child for him.
Though Guo Pu liked beautiful women, he didn’t like leaving seed. Shocked, he fled that very night. He quietly gossiped with Fu Tinghan: “I wonder how many of his five sons are actually his, or if they’re all borrowed seed. Unfortunately, I only saw one at the time. By coincidence, judging from physiognomy, that young man was not his biological son.”
Fu Tinghan: …
He couldn’t help asking Guo Pu, “You’re telling me this—aren’t you afraid I’ll spread it?”
Guo Pu looked at him with disdain. “Besides Zhao the General, who else could you tell? This is such a small matter—tell if you want.”
Actually, when he told Fu Tinghan these things, wasn’t he unconcerned about Zhao Hanzhang knowing? This was, after all, another way of transmitting information.
So this left Zhao Hanzhang with the impression that he was selectively tight-lipped.
Meeting Zhao Hanzhang’s gaze, Guo Pu defended himself: “For such major matters, my mouth is very tight, alright?”
Only then did Zhao Hanzhang let him off.