"Let's suppose this," Bingdi began. "You're a profit-driven merchant, and your goal is to make money and minimize losses. Now tell me if the method to make glass is made public, what would you do?"
Her premise was clear. Tang Chen didn't need to think too long before replying, "If I were a merchant, I'd mass-produce glass." He was sharp and didn't let personal ideals affect his reasoning—he simply roleplayed the part of a profit-seeking businessman.
"Now tell me, do you think there are more profit-driven merchants in this world, or more who have the good of the people in mind?"
"Of course the former."
"Then we've reached a conclusion. If the glassmaking method becomes public knowledge, a huge number of merchants would start mass-producing it. You agree with that, don't you?" Bingdi had become adept at these kinds of logic exercises—she and Chengying had often played such reasoning games when bored over the past year.
Tang Chen nodded. There was nothing to argue; anyone could see the kind of profit potential this presented.
"So here's the problem," she continued. "With so many merchants making glass, and the manufacturing method being relatively simple, the market would quickly become flooded. Now what do you think will happen then?"
"Well, with more sellers, competition increases. So prices would naturally drop. That benefits ordinary people, doesn't it?" Tang Chen seized the opportunity to press his point.
But Bingdi smirked inwardly. She had heard this story from Chengying before. Watching Tang Chen walk into her trap without realizing it brought her a strange sense of satisfaction.
"So, you believe glass prices would fall low enough for commoners to afford?"
"Of course! I mean, if I produce a ton of glass, and others do too, the only way I can sell is to lower the price."
Tang Chen had never lived through an economic crisis, so he didn't grasp the deeper issues.
"But you're ignoring something," Bingdi said. "From your workshop to the market, there are transport costs. Glass is fragile, so it's expensive to transport. If you sell it cheaply enough for commoners to afford, your shipping cost could exceed your selling price."
She turned to Chengying with a smug look, as if asking for praise: Look, I've already learned to apply what you taught me!
Chengying reached out and gently rubbed her head in encouragement. "So, when you're faced with the issue little Bing just raised, what would you do?" he asked Tang Chen, smiling.
"I..." Sweat had started to bead on Tang Chen's forehead. A voice in his heart was whispering a horrifying answer—one he didn't want to accept. "I'd... I'd try to sell the glass cheaply at my workshop, and let buyers come to pick it up themselves to cut losses. Or maybe..."
"No, you wouldn't," Bingdi interrupted flatly. "You're a profit-driven merchant in this scenario, not a kind-hearted philanthropist."
"I..." Tang Chen was stunned. That voice inside him was growing louder. If he were a ruthless merchant, then—yes, he would do that. The rationale made too much sense.
"You'd take a hammer," Bingdi said bluntly, "and in front of everyone, you'd smash your inventory to pieces—reducing your stock to glittering shards rather than sell it cheaply to the poor. That's how you'd keep prices stable and avoid future losses."
A bead of sweat slid down Tang Chen's cheek, splashing onto the glass table. It refracted the light like shattered crystal—beautiful, but sinister. Like the splinters of glass under a hammer's blow.
"Ease up, don't scare the kid off," Chengying said, poking Bingdi's forehead with a finger. "There aren't many soul masters with a heart like his. If you scare off a promising one like this, wouldn't that be a shame?"
Tang Chen wiped the sweat from his brow. He might be straightforward, and the blow to his worldview was heavy—but he came from one of the top clans. He quickly regained his composure.
He stood and bowed respectfully to Bingdi. "Please forgive my offense, Lady. I didn't know you possessed such broad knowledge and insight. I sincerely apologize. Might I have the honor of knowing your name?"
His choice of words—"broad knowledge and insight"—might've been a bit off, but it flustered Bingdi nonetheless. She'd merely repeated a story Chengying had told her, and didn't consider herself all that knowledgeable. Flustered but pleased, she replied with a hint of pride:
"You're forgiven! Honestly, I just learned this all from my brother. Just call me Cheng Bing." Since they didn't look like a couple, they introduced themselves as siblings in public.
Having earned Bingdi's forgiveness, Tang Chen turned to Chengying and gave a deep bow. "Master Cheng, please instruct me! I know you must already have a solution in mind, or you wouldn't have constructed this argument. Please teach me!"
Chengying studied him for a moment, growing more satisfied the longer he looked. The boy might be impulsive, but he had brains, knew right from wrong, and had extraordinary talent. On top of that, he had a strong sense of justice. Truly a perfect candidate for a disciple. And just because Tang Chen came from a clan didn't mean he couldn't take a second teacher...
"Alright then," Chengying said. "If you take me as your master, I'll teach you the solution to this problem. But let me warn you up front I won't be teaching you cultivation techniques. I'm not a fighter."
"Uh..." Tang Chen hesitated. In the Douluo Continent, taking a teacher wasn't a light decision. There wasn't a strict "one master for life" rule, but taking multiple masters still raised eyebrows. And Chengying had said he wouldn't teach him how to fight, wouldn't help with soul rings... Unlike Dugu Bo, Tang Chen wasn't in mortal danger and thus had more to consider.
This was a decision that could affect his entire life. No matter how brilliant Chengying's mind was, this world still respected strength above all.
Seeing the hesitation, Chengying realized he had to show some real substance if he wanted the boy's commitment. He called out toward the next room, where Dugu Bo had taken over the lab:
"Bo, I've found a sparring partner for you. It's time to test your latest research."
Then he turned to Tang Chen. "Dugu Bo is my first disciple. He's learned a portion of my knowledge and developed a battle style suited to his own abilities. You can have a one-on-one Soul Duel with him. Then make your decision."