To Tian Yanzhen's surprise, their conversation lasted for more than three hours.
This greatly pleased him.
For mathematicians like Zhang Yuantang, engaging with a younger colleague in discussing mathematical issues isn't about giving face or listening to their brags; it's about addressing meaningful questions.
The crucial point is that the questions Qiao Yu raised made him feel that answering them was worthwhile.
It's akin to a teacher instructing a student.
If a student constantly asks questions that are too simple and self-evident, the teacher won't perceive this student as diligent.
The teacher might wonder whether the student is paying attention in class; the response would be unenthusiastic, maybe even perfunctory.
But if the student asks valuable and insightful questions, it can engage the teacher's interest and make them willing to spend time discussing with such a student.
