I studied abroad in modern times

In order to prove himself, Old Man Bai took Zheng and Fa to another room.

The door of this room has been closed all year round, and Zheng Fa and the others have never come in.

The room was not big, about ten square meters. There was a row of tall bookshelves against the wall. The books on the bookshelves were arranged in an extremely messy manner. There were also several half-opened books spread out on the floor and on the chairs.

At a glance, he knew that this sloppy study belonged to this lazy old man.

The only difference in the painting style is the desk in the corner of the room by the window. There is nothing else on the desk except a thick stack of paper and a pen holder full of pens.

The strangest thing is that the stack of draft papers is stacked neatly, like a smooth piece of tofu.

"Is this your new book?" Tang Lingwu also saw this special pile of drafts.

Old man Bai became humble at this time: "It's just a thought of mine. I have been writing it for several years."

He turned to Zheng Fa and said, "I really don't have that much time. I made an appointment with someone else to write this book before I retired, but it turned out that I haven't finished it even after five or six years of retirement."

"The People's Publishing House really called me to urge you. I'm not bragging..." Facing the suspicious looks from Zheng Fa and the others, he said, "At most, I was bragging about one or two...five, six, seven or eight."

Zheng Fa looked at the obviously different desk and nodded: "You really value this book."

"It's not that important. As I said before, I am the elder in mathematics." Old Man Bai touched the draft paper on the table, thought for a while, and asked Zheng Fadao: "You know, why I have always been unwilling to teach You?"

"Am I a slow learner?"

"Well, stupidity is also one of the reasons." Old Man Bai has always been straightforward and despised Zheng Fa's IQ.

"Because I have to take the college entrance examination now?" Zheng Fa guessed again.

"There is also this reason, but the main reason is that you are not the kind of person who does mathematics."

Zheng Fa was startled and didn't quite understand why the old man said that.

"I'm not saying there is something wrong with your character, but you shouldn't be too purposeful when doing mathematics. And you..." Old Man Bai glanced at Zheng Fa: "Do you want to learn topology? Or do you want to learn topology? Or do you do it for those weird things? pattern?"

Zheng Fa frowned.

"Isn't it better to be more practical?" Tang Lingwu muttered.

"What is mathematics?" Old Man Bai suddenly asked.

"ah?"

"The fundamentals of mathematical research are things that don't exist." Old Man Bai said to the two of them: "Do imaginary numbers exist? Do natural numbers even exist in nature? Can points, lines, and surfaces in geometry be found in nature?"

Zheng Fa didn't speak. He still didn't understand what the old man wanted to say, but Old Man Bai seemed to have found the feeling of being a teacher in the university:

"Mathematics is essentially a set of abstract, non-existent axioms. To a certain extent, you can think of it as a set of purposeless game rules invented by humans. It just happens that this set of rules can explain some aspects of the world. thing,” he gushed.

"So many theoretical mathematicians look down on applied mathematicians. We have agreed to be the mother of science together. Why are you so weak like..." Looking at the young faces of Zheng Fa and Tang Lingwu, the old man Bai said, She swallowed the indecent word on her lips and changed her words. : "Women who have fallen off the mark."

Seeing that Zheng Fa still didn't understand, Old Man Bai made it clearer: "If you are learning topology for those patterns, then let me ask you, have you ever thought about whether topology can really analyze all these patterns? "

Zheng Fa nodded.

"This is the weird thing about science. You are right ten thousand times and you are not sure you are right. If you are wrong once, you are really wrong. At that time, do you still want to learn topology from me?"

Zheng Fa understood what he meant. The old man was beating around the bush and was still trying to persuade him not to sacrifice the good for the weak.

"I want to learn, even if I am slow to learn." Zheng Fa said slowly. Even without these symbols, he was still very interested in the knowledge of this world.

"Then I suggest you learn from me." Old Man Bai saw that his expression was firm and did not look like he was lying. His expression was a little relieved, and he comforted Zheng Fa in a rare way: "It's okay to slow down, you don't have all the knowledge in high school." Mastery, topology is a second-year undergraduate course at Beijing University. You must have at least the knowledge of a freshman undergraduate before you can really get started. It is actually normal to be slow now. "

Old Man Bai meant well, but Zheng Fa still refused:

"But I still want you to help me analyze those patterns."

Zheng Fa thought very clearly that he was interested in mathematics, but he only used it as a tool.

Just like old man Bai's brain.

"I really don't have that time!"

Zheng Fa turned to look at Tang Lingwu on the side, pointed at her and asked, "I remember you always said that she has already learned college courses?"

"Um?"

"Since I have to start in high school, why don't I learn from her?"

There is no problem that cannot be solved by borrowing your brain. If it doesn't work, then borrow another one.

Tang Lingwu was stunned for a moment and pointed at herself: "Me?"

"I'll teach you martial arts, and you'll teach me math, okay?"

Tang Lingwu looked at Old Man Bai hesitantly.

Old Man Bai frowned, but did not deny Tang Lingwu's ability: "This is also a way. If you can't teach it, just ask me. In fact, if you teach him, you will greatly improve yourself. Comprehension of those knowledge points is just wasting your time..."

"I teach! I want to learn martial arts!"

"Don't you want to?" Old Man Bai hummed.

Tang Lingwu didn't speak, she just smiled with her lips pursed.

Zheng Fa took out the draft books with a smile: "So which one should we start with today?"

Old Man Bai was stunned.

He pointed at Tang Lingwu: "She has become your teacher, and she can practice martial arts."

"Yes."

"In the future, she won't scold you, and I can't scold you. Not only will you not be scolded, but you will also have a beautiful girl as your teacher, and me as your worker."

Zheng Fa smiled: "It seems so."

"And I, not only have to work for you, but I also lose the joy of scolding you?"

This reasoning process is so impeccable that it makes Old Man Bai look desperate.

"At least you have learned a lesson." Zheng Fa patted Old Man Bai on the shoulder: "Next time, don't make a fuss about dropping out of school."

...

Because he had to teach Tang Lingwu to practice martial arts, Old Man Bai's home was no longer open.

Several people came to the small open space where Old Man Bai witnessed Zheng Fa getting started with Songhe Zhuang.

Old Man Bai continued to practice Songhe Zhuang bitterly, and his expression was much more serious than before.

Zheng Fa stood in front of Tang Lingwu and instructed her to stand still. The two were very close to each other, and the tip of his nose was tickled by the other's hair. There was a faint fragrance coming from the little girl.

He was not affected, and quickly gathered his mind, and then he found the difference in this world - after practicing "Spirit Crane Body", once he circulated the Qi in his body, he would feel a force in the void echoing with him in the Xuanwei Realm.

But this world doesn't have it!

The difference made Zheng Fa guess.

"Zheng Fa, you... smell so good!"

Hmm?

Tang Lingwu seemed to think that his words were too vulgar, and her eyes wandered.

Zheng Fa's eyes fell on her seriously, and his eyes explored, as if he wanted to see another old friend from her face:

... Gao Yuan, is that you?

...

"Zheng Fa! I found something strange!" Gao Yuan saw Zheng Fa, trotted to his side, stretched his head in front of Zheng Fa, and seemed to want to whisper something to him.

"Stop, stay away from me." Zheng Fa closed his eyes.

"?"

"I'm not used to you suddenly becoming so ugly."

Gao Yuan touched his confused face, quickly put aside his confusion, and whispered: "I haven't changed, the Seventh Young Master has changed!"

"Changed? What has changed?" Zheng Fa was also a little curious.

"Become..." Gao Yuan seemed to be a little difficult to describe, scratching his head: "Become, a little like me."

...What a coincidence, I also know someone who has become a little like you.