Ning’s classroom had no projector for the first twenty minutes.
She had booked a training room at a technical college near Shenzhen, but the display adapter did not fit the older screen. The students looked at her, waiting for someone to repair the connection.
“Good,” she said. “Our first lesson is that a tool which needs a cable you don’t have is not currently available.”
A few students laughed. Others opened their laptops, ready to search for a workaround.
She drew three columns on the board: claimed function, tested function, responsibility. Then she described a familiar factory example without naming the customer. A forecasting system predicted an evening demand peak accurately but too late for an operator to act safely.
“Is the model good?” she asked.
The students disagreed. One said yes because its error was small. Another said no because the decision had already passed. A third asked what the model had been contracted to do.
Ning pointed to the third student.
“Now we can begin.”
The course was funded jointly by Henglan and the college under terms that allowed Ning to discuss unsuccessful examples without exposing customer records. The company hoped to hire graduates. Ning insisted that the classes teach methods that would remain useful even if students never worked for her employer.
She invited Yanchuan to lead a session about uncertainty. He brought the anonymous plots from Han Rui’s workshop and an example of dependent weather errors. He expected to explain equations. Instead the students wanted to know how to disagree with a manager who demanded a single confident number.
“Write down what the number means,” he said. “Show which decision depends on it. Name the evidence you don’t have.”
“What if the manager still insists?”
“Then you have to decide which claim you can sign. That may have a cost.”
The room grew quieter. He did not pretend a good technical answer protected a junior employee from every consequence.
A student named Lin Ning—not related to the family—asked whether a reviewer’s refusal could be recorded without branding the reviewer difficult. Ning said the organization would have to create that protection and demonstrate that it worked. An interface alone would not do it.
They discussed examples of stop authority, escalation routes and independent checks.
In the workshop exercise the students received a small model with a deliberately misleading training dataset. One group achieved an excellent score by using a field that revealed the label after the event. Another group removed the field and reported a worse score with a defensible evaluation method.
Ning asked which team should be paid.
“The second,” most students answered.
“Why?”
“Because the first sold tomorrow as if it were today.”
Yanchuan thought of the family chronology and smiled despite himself.
After class a student approached him privately. Her father worked in maintenance and had been told that predictive systems would soon make most experienced technicians unnecessary. She asked whether the new tools made apprenticeship pointless.
“No,” he said. “But training may have to change. We need people who can understand what the system does, recognize what it misses and maintain the equipment beneath it.”
He told her about Ravi in Pune without sharing identifying details or pretending his example settled the future of every occupation.
Ning joined them and offered to arrange a supervised visit to a participating workshop, subject to the host’s permission and safety rules. The student accepted.
That evening Guo asked Ning whether the course had generated recruitment leads.
“Some,” she said. “It also made our own engineers explain their assumptions to people who weren’t afraid to ask simple questions.”
“Was that pleasant?”
“Not especially.”
He laughed.
Henglan agreed to repeat the course with a clearer agreement about teaching time and access to examples. Ning required the company to pay for preparation rather than treating education as unpaid publicity.
At home Yanchuan told Jianming about the students.
“Did you learn anything?” his father asked.
“I was teaching.”
“That wasn’t what I asked.”
Yanchuan described the student who had asked about the cost of refusing an unjustified claim. He had given her a technical answer and wished he had a better practical one.
“Then you learned where your answer stops,” Jianming said.
The next week Ning returned to the college with the proper adapter. The projector worked. She kept the board with three columns anyway.
At the end of the course every student submitted a short report about a system’s limits and the person responsible for a decision it supported. The grades rewarded clear evidence, not the most impressive predictions.
Yanchuan read several with her after class. One student had written that uncertainty was not a flaw to conceal but a condition to be managed.
He underlined the sentence, then asked whether the student had cited the measurement it described.
Ning laughed. “You really are impossible.”
“Only if the report asks me to sign.”
She passed him the next paper. This one had a beautifully drawn diagram and no source for the measurements. Ning watched him find the missing note before he reached for the pen.