Chapter 81 Walnut Nourishes the Mind

The fame of the Mohist youth once again spread throughout Chang’an. Yet this time, Mo Dun’s rise to renown was entirely unintentional.

Zhu Mingjun, bedridden with injuries and consumed by boredom, was suddenly struck by inspiration and achieved a breakthrough in understanding the parabola.

“No wonder people of later generations always say, ‘To succeed, one must first endure loneliness,’” Mo Dun mused inwardly.

To Mo Dun, the concept of the parabola was still rather rudimentary—merely the upright axes, the starting and ending points, the apex, and now the axis of symmetry that Zhu Mingjun had added in his flash of insight.

Yet, in this era, it was an extraordinary achievement. When the Zhu family received the news, they were overjoyed—so much so that many grey-haired elders hurried from their ancestral home in Fanyang to Chang’an.

The elders of the Zhu family, together with several renowned mathematicians of Chang’an, solemnly announced that the direct descendant, Zhu Mingjun, had discovered the parabola.

At a time when the field of mathematics had stagnated, this was an event of great importance in the literary circles of Chang’an, and the Zhu family’s reputation resounded through the city once more.

“No wonder the Zhu family is famed for its mathematical prowess! Their ancestor, Zhu Chongzhi, calculated pi, and now his descendant, Zhu Mingjun, has developed the theory of the parabola!”

“Whoever says the Zhu family’s methods are obscure and not worth learning must simply lack the necessary skills.”

“I heard that Zhu Mingjun is only fifteen. Give him time, and he’ll surely rival his illustrious forebear, Zhu Chongzhi.”

“But I heard that Zhu Mingjun’s inspiration for the parabola came when the Mohist youth hit him with a walnut,” someone said mysteriously.

“Impossible!” gasped the listener, eyes wide in disbelief.

“I have a friend in the Imperial Academy; it’s no secret there. Everyone knows the story, and they’ve even witnessed the Mohist youth helping Zhu Mingjun demonstrate the parabola with a game of cuju.”

For a time, rumors ran wild in Chang’an. The tale of the Mohist youth striking Zhu Mingjun and awakening his genius became the city’s latest sensation.

When someone finally asked the elders of the Zhu family about the matter, the white-haired patriarch flatly denied it.

“Zhu Mingjun did indeed attain enlightenment on the parabola from the walnut tossed by the Mohist youth, but he was not struck awake by it.”

The patriarch’s words confirmed that the Mohist youth had indeed thrown the walnut, yet most people refused to accept such an ordinary story. How could it compare in allure to the legend of Zhu Mingjun being struck into brilliance?

“If the Mohist youth hit me with a walnut, maybe I’d gain sudden insight too. Who knows, I might invent oxygen overnight and become fabulously wealthy!” someone daydreamed.

“Hah! You? Even a stone couldn’t knock sense into you!”

Still, some refused to give up. They often loitered around the Mohist youth, making Mo Dun so uneasy that he would tuck his hands into his robes, prompting the disappointed onlookers to disperse.

“I say it wasn’t the walnut blow that did it, but the walnut’s brain-boosting properties that sparked Zhu Mingjun’s genius,” someone speculated.

“Yes, yes! The Mohist youth must love walnuts, which is why he always has them at hand. Just think how clever he is—he invented the secret of keeping fish alive, the curved plow, the seed drill, and artificial incubation. Where does all that brainpower come from? It must be the walnuts!” a scholar in black exclaimed, suddenly convinced he had uncovered a startling truth.

“Hey! Where are you going?” the black-robed scholar called after his companion, who suddenly dashed off.

“I’m going to buy some walnuts for myself!” came the distant reply.

“Wait for me! I need some too!” The black-robed scholar hurried after.

The rumor that walnuts could enhance intelligence rapidly swept through Chang’an, and soon walnuts sold at a feverish pace.

“Getting hit by the Mohist youth is risky—you might end up daft, but eating walnuts can’t hurt,” many reasoned.

Parents whose children struggled with their studies crowded the markets to buy walnuts, hoping to bolster their offspring’s minds.

Now, if you brought a basket of walnuts as a gift to someone’s house, the host would welcome you as an honored guest, offering the best food and drink.

“Crack, crack!”

Three guards pounded away at walnuts, while Qin Huaiyu and his two companions stuffed handfuls of kernels into their mouths, the shells soon strewn across the floor.

Their grand project—the hot air balloon—had reached an impasse. They faced a critical problem: air leakage. With the walnut craze sweeping Chang’an, the three decided to fortify their brains with extra walnuts.

It was little wonder they were so eager. They and Zhu Mingjun had once received Mo Dun’s guidance together, yet not long after, Zhu Mingjun alone had achieved fame and success.

The three, aside from scaling up the Kongming lantern many times over, had made no real progress.

Stubbornly convinced this was their chance at eternal renown, they refused Mo Dun’s direct assistance, insisting only their family craftsmen help.

“Any ideas?” Qin Huaiyu turned to Cheng Chumo.

Cheng Chumo grabbed a handful of walnut kernels, chewed thoughtfully, then shook his head.

Qin Huaiyu was so frustrated his nose nearly twisted out of shape—what was the point of all that thinking?

Even as the walnut shells piled up, the trio remained stumped by the balloon’s leaks.

“It must be those walnut merchants spreading nonsense. I’ve eaten so many and it’s done nothing!” Qin Huaiyu kicked the shells in annoyance.

Mo Dun rolled his eyes. “Walnuts only look like brains; they won’t make you smarter. Don’t trust those unscrupulous merchants.”

“So there’s no benefit at all? Surely you didn’t become so clever just from eating walnuts?” Yuchi Baolin chimed in eagerly. Being the slowest among them, he was always keen on anything that promised to boost intelligence.

He had bought the walnuts—three sacks full—and the three of them had only managed to eat about ten pounds in an afternoon.

“I just like the taste. If you want to know their benefit—well, maybe a little,” Mo Dun replied after some thought.

The trio tugged their ears and listened intently.

“They stave off hunger, if that counts,” Mo Dun said with a mischievous smile.

“Get lost!” the three shouted in unison.

“Mo Dun, why don’t you hit me with something and see if I get inspired enough to solve the balloon problem?” Cheng Chumo said, bracing himself like a martyr headed to his doom.

“Your skull’s too thick, more like elm wood than anything. A walnut wouldn’t work—maybe a brick would have a chance!” Mo Dun hefted a green brick, grinning wickedly.

Cheng Chumo leapt away in alarm. He might not be clever, but he wasn’t a fool—one blow from that brick and he’d certainly split his head, if not gain enlightenment.

“How can we stop the leaks?” Qin Huaiyu sighed in despair.

Their hopes of making history, of standing out among Chang’an’s young elite, hung in the balance.

“If you want to solve the leak problem, I do know someone who might help,” Mo Dun mused, thinking of the old farmer near the Mohist Hospital who could collect a whole bottle of mysterious gas.