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The Poetry of Logic

Chapter Text

“Atem, you’re such a pretty idiot.”

“My beauty is a perpetual tyranny, Aibou.”

Yugi rolled his eyes at his brother, who conveniently ignored the idiot part. He bit into a fry, leaving a plop of ketchup on his own class schedule paper in front of him.

“It’s still vanity if you’re complimenting your own twin.” Anzu elbowed him in the ribs.

“It wasn’t a compliment!” Yugi said.

Atem hid his smile behind a sip of his beer. Yugi and Anzu had been together for years now, but he still blushed whenever she touched him.

“What’ja pharaoh boy do this week, Yuge?” Jou piped up.

“That whole pharaoh thing was only funny when Atem was in Egypt last semester, don’t keep feeding his already enormous ego.” Honda said.

“Yeah, it lives in his hair, that’s why it’s so huge.” Otoogi said.

Everyone laughed, even the usually quiet Ryou. Yugi made a show of snatching Atem’s schedule and reading it to Jou.

“Advanced Latin: Cicero, The Ethics of Love and Sex, Current Topics in Contemporary Philosophy: Almost everything concerning the concrete part of reality and last but most certainly not least…” Yugi’s eyes narrowed. “Introduction to Mathematical Logic taught by—and I cannot possibly stress this fact enough—Seto Kaiba.”

“Ain’t he dat asshole who failed you in Calc 2 sophomore year?”

“Yeah, he is. And what Atem doesn’t seem to realize is he won’t meet the requirements to graduate in May when Kaiba fails him, too.”

“I don’t fail anything, I only win.” Atem snapped.

“Look, Atem… You know I always have full faith in you but this is a class, not a card game. It’s not too late. You can still switch to literally anything else.”

“Is he young?” Mai asked. She was still waiting tables since her shift wasn’t over, but must have come by to see what all the commotion was about. “I have complete confidence you can seduce him to make the grade.”

“Thanks for the moral support, Mai, I’ll be sure to bring it up for class discussion in the ethics of love and sex first.”

Yugi groaned. “Don’t give him any ideas.”

“Why did you sign up if you knew how this jerk treated Yugi?” Anzu asked.

“The other intro math classes were huge lectures with hundreds of people, this class only has 25 registered.” Atem gave a casual shrug.

“That didn’t strike you as a major red flag?” Otoogi said.

“Well, the summary looked more tolerable than anything else offered,” He read from the paper again. “A historical examination on the evolution of mathematical proof and argument from Plato to Descartes to Russell. It sounds more like philosophy than math.”

“Are you convincing us or yourself right now?” Honda said.

“There’s really no changing your mind once it’s made up, is there?” Yugi surrendered finally.

“I would die anywhere, mountain or molehill, to prove an argument.”

“Please remember this moment in two weeks, Atem.”



Monday. 8:03 AM. Late. With coffee.

Atem was morally opposed to early mornings and his definition encompassed anything before 11 AM. He found this was the sole topic his compatriots in the philosophy department held unanimous opinion on, professors included. Evidently, mathematicians did not share this sentiment.

He’d never been in the math building before, but he’d envisioned it decorated with impersonal austerity. Maybe flashy, renovated black and white minimalist décor with cold metal accents every bit as rigid and inflexible as these people seemed to be. It wasn’t.

Everything looked older than the dirt it was built on and the corridors had a musty library-book smell. He walked past a study area with worn-out wooden tables parked with mismatched ladder back chairs. Some Greek nonsense was scribbled hastily in several different sets of handwriting on an enormous chalkboard between tight-packed bookshelves.

Atem parsed the room numbers, not missing the stray chalk-dust finger prints decorating every door. He heard a muffled voice at the end of the hall and strode in, unperturbed that the class had begun without him.

“I assumed you’d know better than to show up to my class late by now, Yugi, but I suppose you truly are nothing but an incorrigible fool.”

Atem felt his blood boil at the comment, both at being confused for his double and on behalf of his brother for the insult. He fought the urge to snap back and looked up to meet an equally livid set of piercing blue eyes.

Oh no.

“Nice try, but you’ve caught the evil doppelganger today.”

Oh, gods, c ould the fates truly be so cruel?

“Don’t insult my intelligence, Yugi.”

No. There was no way he deserved this torture.

“Wrong twin, asshole.”

Yugi had omitted one critical detail in all his descriptions.

“Don’t think I’m as gullible as those dweebs you call friends. Don’t you know who I am, or do you need a reminder?”

Kaiba was young.

“Clearly, the problem is that you don’t know who I am. Atem Mutou. Check the roster.”

And Kaiba was hot.

The name must have registered with him, and Atem tossed out a cocky grin. On the inside, he felt dunked in ice water as Kaiba’s narrowed glare raked him over from tip to tail, assessing the subtle differences between himself and Yugi. Taller posture. Tan skin from his semester abroad. Angular eyes, less violet and more red. Kaiba conceded.

“Your little detour has already cost us six minutes which is $750 dollars of tuition between 25 people, and more importantly, six minutes of my life I will never get back so let’s move on and pretend this nonsense never happened.”

Atem watched Kaiba stalk back to the board before scanning the room for a seat. As it always happens when one is late on the first day, the only open chair left was front and center. Marvelous. A copy of what he assumed was the syllabus that had already been handed out was on the desk. All that was written was the title of the course and an excessively long listing of academic articles.

“I presume many of you were thrilled to see no textbook requirement for my class, and I will be equally pleased to disappoint you with some bad news. This is a reading class. If you do not do the readings, you will fail.”

Kaiba picked up a piece of white chalk that matched his skin tone and raked the edge down the board over and over with a series of pleasant skritching sounds. Satisfied with the point he’d worn in the surface, he began to write.

“Homework will be worth 10% of your grade. If you are late to class, you receive no credit. If you do not support your answers with well-written proofs in complete, English sentences, you receive no credit. Make no mistake, it may be worth only 10%, but if you do not finish and understand the homework, you will fail.”

Atem was growing more confused by the minute. This was a math class. Last time he took math, which he would be the first to admit was the algebra class he flunked junior year of high school, he recalled virtually zero reading and even less essay writing. Only a vast sea of meaningless letters and numbers and other hieroglyphs.

“Cheating of any kind, most notably plagiarism, will not be tolerated. Do not attempt to do so. I assure you, I will know. Not only will you fail, but you will be thrown out of this University so fast your head will spin.”

Atem had his notebook and pen out on the desk, but was too enamored with watching Kaiba’s pale, manicured fingers contrasted against the blackboard to write anything down.

“I hold office hours at 6 AM on Mondays, Wednesdays, and Fridays. If you losers can’t wake up that early, I suggest you become intimately acquainted with stack exchange. I do not entertain questions over email.”

Atem withheld a groan. As if class at 8 AM wasn’t enough. This guy had no concept of too fucking early.

“I enforce a dress code. If you can’t muster up enough maturity and self-respect to show up in something more professional than pajamas, then you can leave my classroom.”

Fine, fair enough. Kaiba himself was certainly a sight for sore eyes. He was dressed in the ubiquitous twenty-first century academic smart casual uniform but bore every mark of crippling detail-oriented neurosis. The sleeves of his classic blue oxford weren’t haphazardly shoved up over his elbows, but folded with calculated precision. The shirt must be professionally tailored, and tapered just right at the waist to allow for no awkward pooling over the belt. Even the legs of his dark-wash denim broke with proper measure on his scuffless brown boots. No single hair on his sleek sable head looked out of place.

“These are my ground rules. You will find they are quite strict. Do not attempt to bend them, or you will be broken.”

Atem wanted to kick himself for thinking the last part sounded oddly alluring. No. Absolutely not. All signs pointed to Kaiba being a contemptible control freak at best and a possible sociopath who mistreated Yugi at worst. Also his professor. Also probably straight.

“We will skip introductions, frankly I don’t care to learn your names. Half of you will drop this class before February. Those of you stubborn enough to stay are unlikely to leave an impression.”

“Most of you are physics majors. I possess a vehement loathing of physicists. You probably think this will be an easy A. You’d be wrong. There will be no magic formulas, no arithmetic, no experimentally derived close-is-close-enough answers, and no fucking integrals to take. May god have mercy on your souls.”

Atem couldn’t mask his small chuckle. Historically speaking, philosophers tend to have a bone to pick with physicists on principle as well, or anyone else close-minded enough to think they have all the answers.

“Many of you are pre-meds. Your flashcards and highlighters and copy-cat wrote memorization will be useless to you here. You’ll have to think for yourself for the first time in your short-lived careers. No, I will not give you a gentleman’s A for your med school application. No, I will not write you a recommendation. No, you are not as smart as you think you are.”

Atem thought perhaps he caught the faint beginnings of a smile on Kaiba’s face before what he said next.

“One of you thinks himself a philosopher. Perhaps you will find yourself pleasantly well prepared for an elegant and rewarding challenge. Do not disappoint. I will endeavor to do the same.”

Kaiba intense and indecipherable gaze caught Atem’s for a fleeting moment before flickering away.

“This classroom is an even playing field. If you have a disdain for arithmetic and frivolous number-crunching, rest assured there will be very little calculation in this class. All that is required to succeed is a pen, fingers to count on, and a brain. All of you have the former. It’s doubtful any of you possess the latter.”

“Now,” Kaiba drew the eraser over the edge of the board, being careful not to coat his dark pants in the flurry of chalk dust before wiping the board clean. “In case any of you were feeling less than motivated this class involves an element of competition. Each day will begin with a question, the first to answer correctly and explain their line of thinkingused to reach the solution gets extra credit points. Consider this a very attractive and generous offer.”

Atem felt his attitude perk up a bit. He loved a good challenge, and had no intentions of losing. Kaiba wrote a question on the board.

Sum every number from 0 to 100.


Wait, didn’t he just say there wouldn’t be any calculating? This felt an awful lot like calculating. And an awful lot like a useless waste of time. Atem heard a smattering of clicking from around the room. Great, he didn’t even own a calculator, and it wasn’t on the list of required supplies.


Atem jumped at the sound of a very expensive graphing calculator being thrown unceremoniously down the hall. The other students slipped theirs back in their bags.

Okay. No calculators.

Kaiba can’t possibly mean to wait around and watch them adding up figures for the rest of class. Although maybe this was some sick life lesson in the tedium of math and the discipline required to practice it? Well, if this was some bizarre sort of mind game then Atem simply resolved to cheat it.

There was no way he was going to do all that work, there was certainly a lazy way out… He started writing. Maybe there was an easier order to add them up in, instead of starting with 1?

“One, two, skip a few, ninety-nine, one-hundred.” He muttered the rhyme to himself, scribbling just that.


0, 1, 2, … 98, 99, 100


0 + 100 = 100

and then…

99 + 1 = 100

and also

98 + 2 = 100

And you could make pairs like that all the way to 50… Well, except for 50 itself since that would be 50 + 50 = 100 and you can’t count 50 twice.

So that meant you got 100 fifty times and 50 once.

(100 x 50) + 50 = 5050


Well “from 0 to 100” is a little ambiguous. Did that mean include 100? Kaiba did seem like a stickler for details. Atem decided to give 4950 as an answer too, just to be safe.

“5050.” Atem was the first to answer. “Or… 4950.”

“Which is it?” Kaiba looked unamused.

“5050 with 100 included, 4950 without. The phrasing of the question was ambiguous.”

Kaiba nodded. “An important lesson in the precision of language. Let’s go with 0 to 100, inclusive.” He handed Atem the chalk. “Explain.”

Atem allowed himself a haughty smirk, feeling pleased that he’d cheated Kaiba’s game. He wrote his little trick on the board. A few members of the class gave a groan of realization, but Kaiba didn’t look even remotely shocked. Atem realized he might have been the one who got played.

“That’s correct.” Kaiba said flatly. “The next one will be harder.” He erased the board and Atem sat back down, feeling a bit vexed at the lack of recognition. He thought his answer was rather sly.

“Our first lesson will be on the topic and Ancient Babylonian and Egyptian mathematics. I will enjoy nothing more than showing you how a bunch of barely literate farmers in the 4th millennium BCE still knew more about numbers than you do.”

Kaiba jumped right into a lecture. On the first day. It would be a long semester.


A/N: The problem in this chapter is based on a famous anecdote from the life of absolute mathematical madman Carl Friedrich Gauss. As a young boy, much to the chagrin of his math teacher who had set the class a busywork task of summing the numbers from 0 to 100, immediately handed in his paper. Once the rest of the class had completed the task, only Gauss' paper contained the correct answer of 5050! The solution Atem gives is Gauss's solution, and the one Kaiba is hoping to receive.