Including Lee Soon-ji, the new researchers and the existing researchers were doing their best to wrestle with numbers in order to solve the tasks assigned by Hyang.
With the increase in personnel, some tasks were easily resolved, but there were also quite a few that were not.
Among the unresolved problems, the most representative one was the correction of the calendar.
Late at night.
"Hmm... I don't understand..."
With a book filled with formulas spread out before him, Lee Soon-ji tilted his head.
What he was troubled by was that there were too many variables in the formulas for correcting the calendar.
"Leap years... leap months, leap days, and the solar terms..."
It would be simple to just add a leap month according to existing customs and adjust the solar terms based on the calendar brought from China, but that would defeat the purpose of revising the current calendar.
"No, that's not right. If I adjust the formulas based on the data I've gathered, the accuracy will increase! But... ugh~"
With a strange groan, Lee Soon-ji stretched and continued to mutter to himself.
"I have to correct it every year, and then I have to correct the corrections every two or three years... This doesn't make sense. The teachings of the sages, as well as the teachings of the Buddha, were truly simple."
In Lee Soon-ji's view, the teachings of both the sages and the Buddha were indeed very straightforward.
As a result, he held the following belief: 'Truth must be simple and concise!' According to this belief, the formula he was currently creating was a complete mess.
He had to correct it every year, and every two or three years, he had to add another month for the leap year, and those two and three years were also variables.
In other words, it was a ridiculous situation where corrections for corrections were repeated.
Because of this unsolvable problem, Lee Soon-ji delayed his departure from the office and continued to ponder deeply.
He absentmindedly moved the teacups beside him and murmured.
"This is the earth... The sun, moon, and stars revolve around this earth, creating day and night..."
Placing the teapot in the center and spinning the teacups around it, Lee Soon-ji suddenly stopped spinning the cups.
"Wait! What if the center of this rotation is not the earth we live on?"
He raised his finger and began to draw an imaginary orbit as he calculated.
Like a madman, he waved his hands and muttered to himself until he reached a conclusion.
"If the center of rotation is the sun, then the formula holds! We can place the sun at the center!"
Lee Soon-ji grabbed a stack of blank papers piled up on one side and quickly began to write down the formulas.
As if possessed by a deity, he wrote furiously until, at one moment, he put down his pen and clenched his fist.
"Indeed! The variables for the variables have disappeared! Hahaha! Uwaah!"
Lee Soon-ji burst into laughter, sounding almost insane, and let out a wild scream.
A pleasure greater than the joy he had experienced before surged through his entire body.
He stood up from his seat, opened the window, and shouted.
"The center of the world is not this earth! This earth is merely a dependent variable!"
Having found the solution through last night's sudden enlightenment, Lee Soon-ji devoted himself to organizing the formulas he had discovered.
Giving up on leaving the office was just the beginning; he even skipped meals frequently, and rumors began to spread among the researchers.
"The eccentric has gone mad!"
Upon hearing the rumors, Jeong Cho and Jeong In, who came to check on the situation, were left speechless at the sight of the piles of papers beside Lee Soon-ji.
"What is this...?"
With shocked expressions, Jeong Cho and Jeong In examined the contents written on the papers.
"Hmm... huh?"
"Ah?"
Being well-versed in arithmetic, Jeong Cho and Jeong In quickly recognized the value of the formulas Lee Soon-ji was writing.
With a tense expression, Jeong Cho turned to Jeong In.
"I will report to His Highness immediately, so you keep an eye on this fellow."
"Understood, my lord."
After some time, Hyang, who had rushed over from District 51 upon receiving urgent news, examined the problematic papers.
The expression on Hyang's face grew serious as he scrutinized the contents written on the papers.
"Damn! This level is beyond me too!"
While others might not have known, Hyang had chosen the humanities in the 21st century due to mathematics.
What he was most confident in was the classical method of solving problems through direct experience.
Although he did not fully understand it, he grasped the general idea and commanded Jeong Cho and Jeong In.
"Immediately prepare the royal physician!"
"Understood!"
"And until this left minister finishes his work and formally reports to His Majesty, keep this matter confidential."
"Understood!"
"And... it seems I have won the debate, right?"
"Ugh..."
At Hyang's question, Jeong Cho and Jeong In groaned.
After the establishment of the research institute and the ongoing revisions of the calendar, a debate had arisen among Hyang, Jeong Cho, and Jeong In.
The topic of the debate was 'The earth is round' and 'The earth revolves around the sun.' Astronomical observations were essential for revising the calendar, and this process led to a clash of concepts.
The debate that 'The earth is round' easily resulted in Hyang's victory.
This was due to the observational report that "The horizon viewed from a high mountain facing the sea forms an arc," along with the assistance of the followers of the religion.
However, the heliocentric theory sparked a lengthy debate, as Hyang, with only superficial knowledge from entrance exam education, found it impossible to refute completely.
As the debate ended in a stalemate, the celestial armillary sphere could not be placed in the exhibition hall of the research institute.
"Ah! The drawbacks of entrance exam education, knowing only the names of Galileo and Copernicus!"
Having lost the debate due to his lack of understanding, Hyang looked up at the sky and lamented the shortcomings of entrance exam education.
A month later, Hyang gathered Sejong and the ministers for a presentation on the 'Calendar Correction.' The one responsible for the presentation was Lee Soon-ji.
To calm his nerves, Lee Soon-ji even took a calming pill and proceeded with the presentation calmly.
"... That is all."
As Lee Soon-ji finished his presentation, Sejong, who had been listening attentively, praised him.
"Well done. Truly a good theory. Crown Prince, what do you think of this left minister's theory?"
"I compared it with the records of previous calendars and the occurrences of solar and lunar eclipses, and there are no discrepancies."
"Then, we can finally say that we have created our own calendar, right?"
In response to Sejong's question, Hyang corrected the wording.
"It is a correction method, Your Majesty."
"Yes, 'correction method.'"
Nodding with a bitter expression, Sejong looked around at the ministers.
"What do you all think?"
In response to Sejong's question, Hwang Hee answered on behalf of the others.
"I believe the calendar correction should be applied and used immediately. However, the problem lies in creating a book for educational purposes. It will inevitably be released to the public, and that could lead to issues. Some sentences need to be omitted."
"Omit sentences?"
In response to Sejong's question, Hwang Hee explained.
"The parts stating 'This world is spherical' and 'The world revolves around the sun.' If not handled carefully, it could become a problem with the Ming court."
"Hmm... That is true."
Sejong nodded at Hwang Hee's observation.
Until now, the worldview had been 'The world is flat.
And the center of the world is China.' However, the theory emerging from the research institute contradicted this.
Yet, omitting sentences did not sit well with Sejong's taste.
Of course, he had to be cautious of the Ming court due to the difference in national power, but he did not like the idea of damaging his pride.
"Is there no other way?"
In response to Sejong's question, Hwang Hee replied again.
"We can emphasize that it is merely a simple principle of nature."
"A simple principle of nature? Hmm... I see."
As Sejong nodded, Hwang Hee added.
"To make that claim, we need solid evidence to prove it. The evidence presented by the research institute is still lacking."
"I see. I command the Crown Prince."
"Yes, Your Majesty."
"You know what you need to do, right?"
"Yes, I will gather more evidence to solidify the theory."
"Good. Then, what should you all do?"
In response to Sejong's question, Lee Jik stepped forward to answer.
"We must make it clear that this is merely a simple principle of nature and does not deviate from the four virtues."
"You understand well. Minister of Rites, your responsibility is heavy."
At Sejong's words, the Minister of Rites bowed his head and replied.
"I will do my utmost to fulfill your command!"
"Then, let us conclude here."
As Sejong declared the end of the presentation, the ministers shook off their seats and exited.
"Haa~."
"Minister Ye, you worked hard."
"Minister Ye, you too have a tough road ahead."
As the other ministers commented, Ye Pan shouted back.
"Really! Why does the Crown Prince have to...?"
"Minister Ye!"
Ye Pan, who was about to say something about the Crown Prince and the research institute, immediately shut his mouth at Hwang Hee's reprimand.
"Unnecessary? Do you really think so?"
"Well, until now, it has been somewhat..."
"Such a frustrating person! Have you forgotten that many suffered because of the inaccuracy of the solar terms due to that 'suitability'? And you still want to be a minister!"
"I apologize."
Under Hwang Hee's criticism, the Minister of Rites had to bow his head.
In Joseon, where agriculture was everything, getting the solar terms right was extremely important.
If the solar terms were not accurate, all the blame would fall on the king, who would have to punish those responsible.
"I know that you and the Ministry of Rites have a heavy burden! But it is the duty of the Ministry of Rites to solve that! How can you only seek comfort for yourselves? If you want to live comfortably, resign and leave! I'm tired of being scolded as a minister! I'm fed up!"
Hwang Hee's last sentence revealed his true feelings.
Thus, in order to avoid conflict with the Ming court, the problematic sentences were removed from the book distributed to the Office of Astronomy.
The original was treated as a top-secret document and stored in a safe.
Since the declaration of the Minister of Rites, the ministers had changed a lot.
No, they had no choice but to change.
They had to change due to Sejong's constant reprimands whenever their work was even slightly unsatisfactory.
At the forefront of this change were the Prime Ministers.
If the ministers of the six ministries or those under them failed to carry out their duties, the Prime Ministers were the first to be scolded.
As a result, the personalities of the Prime Ministers became quite prickly.
Lee Jik and Hwang Hee, of course, and even the kind-hearted Maeng Sa-seong had become accustomed to hurling sharp words whenever their work fell short.
"Wow! Ever since you became a Prime Minister, you've changed! You've become a terrible noble!"
This was the common assessment of the three who had become prickly.
However, the Prime Ministers also had something to say.
"Then do your job well!"
"Why should I be scolded by the king? Am I a scapegoat?"
"If you don't want to be scolded, then don't create situations that warrant it!"
"If you're wronged, write a petition or resign! I said resign!"
Thus, due to the forced changes, the efficiency of the Prime Ministers improved.
A representative example was when they returned after completing the inspection of District 51.
Sensing that Sejong wanted mass production, Hwang Hee had informed Ho Pan in advance, allowing him to prepare records regarding the production of iron to present to Sejong.
As a result of these changes, the Prime Ministers encountered fewer instances of hearing the words they dreaded the most.
"Compared to what I've heard, it's..."
This was the very phrase.
Hwang Hee and the Prime Ministers were currently troubled by one issue.
The issue they were grappling with was 'the supply of iron.' With the decision to mass-produce the matchlock musket and the bomb, the court required a large quantity of iron, specifically low-carbon steel.
Until the Goryeo Dynasty and the early Joseon period, iron was directly collected from the people through a system of iron collection, but due to strong resistance from the farmers, the system had to be changed.
The alternative chosen to replace the iron collection system was to create ironworks near iron mines and mobilize farmers during the off-season to produce iron.
However, this system also had many problems, as forcibly mobilizing farmers led to resistance and a decrease in their motivation.
Ultimately, Sejong's solution was simple.
"Purchase those that meet the specified standards and quality!"
However, the ministers and Prime Ministers responsible for the practical work were troubled.
"There is no budget! No budget!"
In the end, even after brainstorming together, the Prime Ministers could not find a good solution and informed Sejong of the problem.
"Your Majesty, we are trying to implement the measures you have decreed, but there is an issue."
"An issue? Hmm... Is the budget the problem?"
"Indeed."
At the Prime Ministers' response, Sejong clicked his tongue for the first time in a while.
"Tsk!"
However, this time the Prime Ministers had something to say.
"Your Majesty, we are diverting the quantities coming in through the ironworks system to resolve the budget issue, but there are essential parts that must be used, and if we take away that amount, there is little left."
"Your Majesty, the issue of purchasing the insufficient amounts is related to the budget."
"Your Majesty, to resolve this budget issue, we need to address the taxation issue, but preparations are still lacking."
"It's not just the taxes that are the problem. When purchasing iron, we must pay for it, and there are limits to the grains and textiles we can use as payment. To resolve this, currency management is essential, but preparations for that are also still lacking..."
"Goodness..."
Sejong felt frustrated by the Prime Ministers' responses.
He wanted to actively pursue work, but the insufficient capabilities of Joseon were holding him back.
"Let us think a little more."
"Yes, Your Majesty."
After sending the Prime Ministers away, Sejong let out a sigh.
"Haa~. What kind of country is this... not even a good-looking peach..."
Hearing the rumors, Hyang clicked his tongue.
"Tsk! If building up is this difficult..."
Hyang found a blank sheet of paper and began to write.
"The best option would be a state-owned enterprise, right? Pohang Steel! How wonderful!"
Upon receiving the petition suggesting, 'Let us create a state-owned enterprise to manage the supply of iron,' Sejong immediately slapped his knee.
"That's right!"
However, the ministers shook their heads after reading Hyang's petition.
"How can the state engage in commerce...?"
"Even if it's a state-owned enterprise, it seeks profit, so how can the court pursue profit?"
"Tsk!"
Sejong clicked his tongue at the ministers' reactions.
As soon as Sejong clicked his tongue, the ministers tensed up and reflected on their statements.
"How can you think so short-sightedly? If the court produces iron, only the court benefits? Iron is not produced in all eight provinces of Joseon, is it? In regions where iron is produced, prices are low, and in regions where it is not, prices are high, causing hardship for the people. If the court produces iron directly, can't we solve this difficulty? And wouldn't it also resolve the issue of the Han River?"
"Ah..."
"Think a little before you speak!"
Under Sejong's reprimand, the ministers became speechless.