Liu Bin was a high-ranking provincial official serving in the most important province of the Great Xia Dynasty. Under normal circumstances, even during his journey to assume office, he wouldn't have much time to spare—let alone discuss upcoming policies with a teenager.
Perhaps Cheng Jinzhou's exceptional performance had driven Liu Bin to grasp at straws in desperation.
Unfamiliar with politics and relying on his youthful appearance after possession, Cheng Jinzhou shifted slightly and said, "I could personally survey the land without any issues, but the calculus I mentioned yesterday would be too slow to use."
The problem wasn't just about speed. Calculus wasn't some apple Newton obtained from a bruise—beyond applying various formulas, actual calculations required accumulated data that later generations would simply look up in tables. Cheng Jinzhou had no such resources at hand.
Completing all calculus calculations developed over centuries by himself, without supercomputers or other informational aids, was virtually impossible. In other words, 21st-century science had progressed beyond the age of lone heroes making groundbreaking discoveries.
Liu Bin showed clear disappointment, nodding slightly. "Master Liu Kuang suggested establishing aerial coordinates for the entire province's land, but this would require mobilizing over a hundred astrologers for two to three years—though that's already remarkably fast..."
"But too expensive?" Cheng Jinzhou shrugged lightly. Renting six helicopters for an hour rarely exceeded $1,000—converted to silver using grain prices, merely thirty taels. What astrologer capable of flight would work for such meager pay? Even so, modern land surveys wouldn't use hundreds of helicopters—this highlighted the productivity gap.
"Indeed." Liu Bin sighed before smiling wryly. "Never mind, let's just chat casually. Yang Ming, you should go prepare for our journey."
"I do have methods to reduce your costs, though eliminating expenses entirely is impossible." Cheng Jinzhou quickly gathered his thoughts and spoke after brief hesitation. This Transport Commissioner was a genuine goldmine—a nobleman ignorant of mathematics yet closely connected to him, the perfect source for his first pot of gold.
Yang Ming exclaimed "Oh!" and sat back down without regard for propriety, both men now all ears.
From Garrison Commander to Hexi Transport Commissioner, Liu Bin's rapid promotion reflected his youth and towering ambitions. Land surveys, tax reforms, even restructuring the nobility—all part of his grand vision now bottlenecked at the starting line, leaving him too overwhelmed to stand on ceremony.
Like prodigy mathematicians throughout history, young astrologers achieving fame early was common, so neither man underestimated Cheng Jinzhou.
Seeing their expressions, Cheng Jinzhou rubbed his head helplessly. "Do you even understand this?"
"Fetch Master Wu!" Liu Bin reacted swiftly, shouting outside. One purpose of his visit to the Cheng household was borrowing their resident astrologers, and Wu Zong happened to catch his favor.
Cheng Jinzhou used this moment to organize his thoughts. His ring was currently useless—he'd have to trade his meager knowledge for funds to sustain it, a rather pathetic realization.
Wu Zong entered the hall with pious haste, performing a deep student's bow—back bent, shoulders tucked, arms straight. Astrologers lived by their own codes, with intellectual worship paramount among them.
Oblivious to the implications, Cheng Jinzhou left Liu Bin and Yang Ming utterly dumbfounded.
After completing his bow, Wu Zong quietly took a subordinate seat beside Cheng Jinzhou, hands flat on his knees like an obedient schoolboy.
Ignoring this, Cheng Jinzhou blinked as everyone assembled. "Given current circumstances, Master Liu Kuang's aerial coordinate method remains the fastest for provincial surveys."
Liu Bin nodded agreement—without astrologers, large-scale land surveys could drag on for a decade.
"Let me propose two cost-saving alternatives." As Cheng Jinzhou unconsciously mimed holding a brush, Wu Zong swooped like a sparrow to provide a hard-tipped writing brush and paper from his robes, spreading them eagerly across the table.
For unranked astrologers, cutting-edge mathematics represented their greatest aspiration.
Rubbing his nose while writing, Cheng Jinzhou explained, "The most challenging lands to survey are hillside fields and terraces. I've developed an algorithm that improves both accuracy and speed. Imagine a terrace—two surveyors with measuring tapes start from Point A along opposite edges toward Point B, measuring chord lengths at regular intervals while maintaining parallel, equidistant lines..."
As technical terms and numbers flowed, beads of sweat formed on Wu Zong's nose while his face flushed with excitement.
Even in the 21st century, land surveys rarely employed high technology—especially in China, where simple village-level methods worked best.
The Great Xia Dynasty presented different challenges—this wasn't a peasant-dominated society. Vast estates crisscrossed by boundaries and sprawling noble manors required far greater effort to map accurately.
As an advisor with some mathematical knowledge, Yang Ming studied Cheng Jinzhou's diagrams and nodded. "Master Liu Kuang mentioned how coordinate measurements struggle with uneven terrain like this. Your method resolves several issues."
"Now for the second approach." Without pausing, Cheng Jinzhou adjusted his brush. "Regarding coordinate surveys, I have some insights... Could you three keep this confidential?"
"We could submit findings to the Association!" Wu Zong blurted excitedly. "Coordinate calculations represent the pinnacle of mathematics! Any minor advancement could earn you tremendous rewards—perhaps even an official rank! With higher-grade astral arrays, who'd dare oppose you?"
"I have my own plans." Cheng Jinzhou remained firm. "Can you keep this secret?"
Witnessing Wu Zong's deference, Liu Bin regarded Cheng Jinzhou as an equal and vowed solemnly, "I swear upon my name."
"Yang pledges his family's lives as guarantee."
Reluctantly, Wu Zong finally raised his head. "By the Astral Divinity's name!" He added petulantly, "The Association operates on contribution systems—exchanging knowledge is necessary to obtain astral arrays and research."
"That's for later." Cheng Jinzhou had to be cautious. Analytic geometry and calculus formed the twin foundations of modern mathematics—and thus modern science—that no single genius could develop alone. Revealing calculus was risky enough without exposing analytic geometry too.
"Without sacrificing precision, I can measure larger areas with fewer points." Drawing irregular shapes, Cheng Jinzhou continued, "These formulas apply here... Naturally, you should have Master Liu Kuang verify them—but don't mention my involvement."
Though unable to comprehend the equations, Yang Ming nodded repeatedly. "Fewer measurement points mean fewer astrologers needed."
"Exactly." Cheng Jinzhou chuckled. Coordinate surveying was more commonly used in road construction—where flat, unfolded surfaces lacked the ditches common in farmlands. Yet in the Great Xia Dynasty, contiguous fields dominated like South American agricultural nations.
Compared to 17th-century analytic geometry, Cheng Jinzhou possessed overwhelming knowledge—despite being an underachieving physics PhD.