“Seoha!”
After class ended, Seoha, who had been noisily packing his bag and was fully ready to go home, turned around at the sound of someone calling him. Then he ran over with a bright smile.
“Yes! Teacher!”
‘Why don’t kids that age ever just walk normally?’
Yunmi envied that overflowing energy, but found it burdensome too.
Looking at him like this, he was definitely an ordinary elementary school student…
Nowhere on Seoha’s face could she find the particular gloom of an abused child. Nor did he show the arrogance that students who had already finished studying ahead sometimes revealed. Even during addition and subtraction lessons, he participated actively like the other children and worked diligently on dictation.
Of course, this was because Miyeong and Cheolho had repeatedly told him that he had to listen carefully to the teacher during class, but Yunmi had no way of knowing that.
“Did you bring a difficult book in your bag again today?”
At Yunmi’s question, Seoha opened his eyes wide and nodded.
“Yes. I was going to read it during break. The kids don’t play soccer these days because they say it’s hot…”
The way he fidgeted with his clasped hands and glanced toward the door made it clear that he very much wanted to go home.
“Do you have some urgent reason to leave?”
Perhaps embarrassed at having his thoughts seen through, Seoha’s face turned red.
“N-no. It’s not that, but Seoeun is waiting for me. Seoeun is my little sister, and she’s incredibly cute. Mom only starts cleaning and preparing dinner after I get home, too.”
Remembering the baby who had been in her mother’s arms, Yunmi almost laughed. She certainly had been a cute baby.
‘Ah! What on earth was I thinking?’
The tension left her.
Seoha was just a simple, kindhearted country elementary school student. Yunmi decided to quickly set this admirable child free.
“Then will you try solving just these problems? There aren’t many, and if you solve them all, you can go right away!”
“Really?”
Seoha asked, his face lighting up, as if he had expected it to take a long time.
“Of course! If there’s anything difficult, you can just leave it.”
He was certainly a smart child.
It might be an extremely rare case, but among her classmates from science high school, there had been a friend who taught himself middle and high school math from the lower grades of elementary school. That guy was now pursuing a doctorate at UCLA.
He might not be at that level, but if Seoha could perfectly solve even middle school mathematics, Yunmi began to wonder what kind of help she should give him.
Before she knew it, Seoha had taken a character pencil with a duck figure attached out of his pencil case and begun writing down the answers.
Question 1, first-year middle school level.
Proportional expressions and ratio reasoning.
[If 5 cm on a map is actually 2 km, how many km is 8 cm?]
Scratch, scratch.
「3.2 km」
Seoha wrote down the answer in an instant.
‘Mental arithmetic as soon as he saw it?’
Yunmi’s eyes twitched. Then she examined Seoha’s face closely.
The blinking of his eyes had decreased, and his breathing had grown faint. His lips were half closed, slightly curled inward, as he stared at the test paper.
It was certain. Perhaps because he wanted to go home quickly, Seoha had entered complete concentration mode.
Scratch, scratch.
Question 2 was the Pythagorean theorem.
[When a right triangle with a base of 8 cm and a height of 6 cm and a square with side length 8 cm share one side, find the distance from one vertex of the square to point O, the midpoint of the hypotenuse of the right triangle.]
After looking at the problem and thinking for about two seconds, Seoha’s hand moved immediately.
‘No way! This one too?’
Gulp.
Yunmi swallowed dryly.
It was a problem meant to assess thinking rather than calculation. She had even prepared the answer so it would come out neatly. Seoha wrote down the answer as if there was nothing to see.
「5 cm」
Question 3, quadratic equations.
[For the real number m, the following quadratic equation is given: x² + 2mx + (2m - 1) = 0. Find all real numbers m such that this equation has two distinct real roots and the difference between the two roots is 2.]
Seoha’s pencil moved without hesitation. Yunmi watched him, forgetting even to breathe.
In an instant, Seoha recalled the condition of the discriminant and converted it into an equation suited to the problem.
There was no pause. He did not seem to hesitate either. It meant he was 100 percent certain of the answer.
「m = 0 or m = 2」
Yunmi unconsciously covered her mouth with her hand. A sound had almost escaped her.
It was not difficult to solve an equation by simply substituting into the quadratic formula. But the ability to understand the structure of the problem and transform and connect the conditions was extremely special.
Yunmi’s heart pounded violently.
Speed did not matter at all. This kind of structural thinking was not something that could be taught.
Question 4, application of trigonometric ratios.
The calculation was easy, but it required a shift in thinking.
Seoha did not simply substitute values into the problem or rely on formulas.
Eight years old, an age when even struggling through arithmetic would be more than enough, yet structural thinking had already become second nature to him.
And as if it were only natural, he wrote down the correct answer.
Question 5, differentiation.
[Find the real number a such that the difference between the extrema of f(x) = x² + 2ax + (2a - 1) is 2.]
The calculation was short, and his judgment was even faster. Yunmi felt as if she would go mad wondering what on earth was happening inside this child’s head.
Seoha, holding the pencil in his hand, swept his eyes over the problem once and immediately began calculating.
An eight-year-old child grasped the entire flow—derivative, location of the extremum, difference of extrema—in an instant, without getting lost even once.
He read the problem and directly connected the condition and the function in his head. In that process, he did not go through a single unnecessary step.
This meant that Seoha already possessed flawless logic and intuition.
An indescribable emotion flashed through Yunmi’s mind.
Would it feel like this if an elementary schooler drew an elaborate architectural blueprint with crayons? The cold logic contained in those innocent letters was chillingly out of place.
“I’m done, Teacher!”
Had three minutes passed?
Seoha was cute as he held out the test paper, expressing with his whole body that he wanted to go home.
“All right. You got everything right. You may go home.”
She was so shocked that her words came out dry. She thought, Oops, but Seoha did not seem to mind at all.
“Yes! Thank you!”
Seoha bowed deeply with both hands at his belly, then dashed out.
After doing something unbelievable, he showed no sign of expecting even a word of praise, as if it were nothing.
Yunmi stared blankly as Seoha ran out on his short legs.
She fell into thought.
“What am I supposed to do with you?”
Yunmi looked down for a long while at the paper in her hand.
It was something she had never thought possible even in a dream. The gap between reality and common sense was so wide that her mind went blank.
She carefully stored the answer sheet in a file so it would not get crumpled. As carefully as if she were trying not to damage a precious treasure.
Tap, tap, tap.
Yunmi drummed the desk with her index finger.
He was still in the first grade of elementary school.
Needless to say, it was an age that required adult protection. Even if he showed brilliance now, he might lose interest in math at some point. Yunmi had seen countless gifted children disappear like that.
“If he were an ordinary gifted child, that is…”
Seoha was something outside the norm, something that could not be expressed even with the word genius.
At that moment, she felt goosebumps rise all over her body.
Perhaps she was now in a position to influence a great figure who would leave his name in history.
Hssss.
She took a deep breath. Her sense of reality returned.
The fingertips resting on the desk trembled faintly.
For a long while, Yunmi considered the possible choices she could make. But not a single one satisfied her. What was the reason? It was obvious. Because she herself had never been a genius. Therefore, she lacked the basis to judge what the best path would be.
“I’ve decided.”
She would ask a genius about the affairs of a genius. Or someone who had been something close to one.
The burden was too heavy to carry alone.
Ring, ring, ring, ring.
The signal continued for a long time.
—What’s this about? You’re actually calling me?
Only when the ringing was about to end did an uncomfortable voice come through.
“I have something to ask you.”
There was no answer for a long while. Then, with a resigned sigh, he replied.
—Hold on…
* * *
Beep—
Uhyeon hurriedly turned off the recording camera.
Various graphs and formulas were written on the blackboard. What business could his ex-girlfriend, who had not contacted him in years, have with him?
At the words that she had something to ask, Uhyeon strode out of the studio and grabbed a can of coffee from the refrigerator.
Click—
“What is it?”
—Among the students I teach, there’s an incredible genius.
Uhyeon snorted.
“Genius, my ass. You call me after all these years just to say that?”
He was sick of it. That word.
It was the praise that had poured endlessly onto him when he placed second in the International Mathematical Olympiad, in which more than one hundred countries participated. It had been the second-best result ever achieved by a Korean contestant since Korea’s first participation in 1988.
But all of it was meaningless. Such titles were meant only for the very small number chosen by God.
—I know what you’re thinking, but this child is really different. Listen, this kid—
But Yunmi could not continue.
“Stop! If you don’t have anything else, I’m hanging up.”
Was she angry?
A suffocating silence flowed from beyond the receiver. Regret surged up.
‘Damn it. Should I have been nicer? But why did she have to scratch at my sore spot? She knows I hate hearing crap like that.’
While Uhyeon was wondering what to do…
—Petty jerk…
“What?”
A vein stood out at his temple.
—Hey, you petty little jerk!
“You really want to die?”
—How long are you going to keep sulking?
The more he listened, the more his temper rose. Everyone had a reverse scale that should not be touched.
“What do you mean, sulking? Is there even one person among our classmates who earns more than me?”
Last year, he had paid over five billion won in taxes alone.
A top-ranked instructor revered by all parents and exam-takers. To dare say that to Shin Uhyeon, the god of mathematics with the finest education and credentials!
But the next words he heard chilled his heart.
—If you’re that proud, why don’t you come to class reunions?
“…That’s because of you. You think I’d be comfortable seeing my ex-girlfriend?”
—As if.
“Enough. I’ll listen, so tell me again. What did that kid do?”
From the other side, he heard her breathe out as if relieved.
“A first grader in elementary school perfectly understands and solves calculus and analytic geometry with vectors.”
As soon as Uhyeon heard that, he frowned.
“Are you still in Gangnam? The parents of that family must be something else. How hard did they push the kid…?”
There were several children like this every year.
When good DNA combined with inhuman early education, children like this appeared, surprisingly often. Most of them would soon learn their place and go on to medical school.
And if they still could not escape their delusions, they would appear on some gifted-child discovery program and make their faces known. It was ridiculous. As if anyone would acknowledge that.
—No. I’m in my hometown now.
“Okcheon?”
When the two of them had been dating, Uhyeon had once gone down to her hometown with her.
—Yeah.
“You’re saying there’s a kid who solves that stuff in that backwater?”
—I couldn’t believe it either. I called in the child’s mother and talked to her, and she said they’ve never sent him to academies, let alone taught him at home. The child figured it out on his own.
“You’re sure it’s not a lie?”
—Do you think I’d be fooled? I checked several times. Oppa, tell me. I don’t know what to do with this child. Should I contact somewhere like a gifted education center? Or should I look into early graduation? I was thinking about calling teachers at science high schools too…
Uhyeon cut off Yunmi’s urgent words.
“Don’t. You’ll ruin the kid. You’ll just fill the parents’ heads with useless dreams. The student will get arrogant too, thinking he’s something special.”
—Then what should I do? I’m serious, I’ve never seen a child like this in my life.
“That may be true in Korea. Overseas, there are some now and then. Absolute lunatics.”
As if recalling an unpleasant memory, Uhyeon’s face crumpled mercilessly.
—Are you saying I should just leave him alone?
“Of course not. Assuming what you said is true, do you know what real geniuses like him need?”
—Yes, yes. I wouldn’t know, since I’m not a genius.
Even at Yunmi’s sarcastic tone, Uhyeon did not mind at all.
“Overwhelming results.”
—What?
At the unexpected answer, Yunmi was left speechless.