I studied abroad in modern times

After all, Senior Sister Zhang is a self-controlled person. The emotion on her face was only fleeting. She just shook her head and said to Zheng Fa and the others:

"This Xuanguanjian is my master's old thing. It can only be produced by a Yuanying."

"Yuanying..." Senior Sister Yuan blurted out: "Yuanying is so difficult..."

Seeing Senior Sister Zhang silent, she seemed to feel that she had said something wrong, and added:

"Fortunately, Senior Sister Zhang is very talented! Things that are difficult for others are definitely not difficult for you!"

"No, it's a little harder for me than for others." Senior Sister Zhang said softly: "I practiced too fast in my early years, but now I have to pay the price."

Even Zheng Fa nodded at this.

He had heard about Senior Sister Zhang's experience:

It takes at least two or three years to build a foundation with a single spiritual root, but Senior Sister Zhang went straight into the foundation in less than a year.

When she achieved the Golden Core, she had only been in the Dao for ten years.

As a result, her reputation was greatly shaken, and she was regarded as the first person under the Yuanying in the Baixian League.

But for the next eighty or ninety years, she was stuck in the Golden Core Stage and could not make any progress.

She hid in the Mysterious Gate Mirror, and although she escaped the pursuit of the Yuanying of the Great Freedom Demon Sect, she also forced herself into a desperate situation where she could not get out without the Yuanying.

"Zheng Fa, you must remember... Be cautious when building the foundation." Although she was in a difficult situation, Senior Sister Zhang instead reminded Zheng Fa: "I had no experience back then, and I was walking a path that no one had walked before. I didn't understand many things, and I was young at the time, and I was dazzled by the title of the first genius of the Hundred Immortals League."

"Later, when I realized that the Fu Dao Foundation Building Method was not perfect, I consulted ancient books and found that if a perfect path was really created, there would be strange phenomena in the world."

"... Strange phenomena?"

Zheng Fa was a little puzzled when he heard this.

"Not many people know about this." Senior Sister Zhang explained: "The spiritual energy has declined at least five times. No one knows the origin of the method of cultivation. It may have been perfected before the last catastrophe, so the people who create the Tao are extremely rare. In these two catastrophes, there is only one person who really created a unique method of cultivation-"

Zheng Fa twitched his mouth.

He has guessed who it is.

"It is recorded in ancient books that Venerable Tianhe created the method of the natal spiritual treasure after forming the elixir. Now it has become the first method of forming an infant in the Xuanwei world. At that time, the Heavenly Dao was sensitive, and the whole Xuanwei world had strange phenomena. Venerable Tianhe said that the Tao is born and strange phenomena appear."

Sure enough, you are everywhere, Venerable Tianhe!

"When I used the "Talisman Foundation Building Method" to condense the foundation of the Tao, there was no strange phenomenon - perhaps it is because the Talisman Foundation Building Method is just a foundation building method."

"But it is also possible that the Yuanfu Tao that I condensed is defective and cannot be considered a perfect path." Senior Sister Zhang sighed softly: "It's a pity that I only understand it now."

"Practice is always a step wrong and a step wrong." Senior Sister Zhang continued to remind Zheng Fa: "I haven't seen the way to condense the Nascent Soul yet. Even if I condense the Nascent Soul, I am afraid there will be some difficulties in the future - Zheng Fa, if you don't want to be like me, you must be cautious when building the foundation."

Seeing that she is still reminding herself now.

Zheng Fa couldn't help but interrupt her and said: "Senior Sister, are you sure about the Nascent Soul?"

"..."Senior Sister Zhang was silent for a while and said: "The life of the golden elixir is a thousand years. I still have nine hundred years. There is no rush."

"..."

This seems to be confident.

In fact, it is too unconfident.

The life span of Qigong practitioners in Xuanwei Realm is not much different from that of ordinary people, only about a hundred years.

After building the foundation, they can live to three hundred years old.

The golden elixir lives for a thousand years.

The Nascent Soul is a big leap, and I heard that the master is already about ten thousand years old.

But... these are all ideal life spans.

As far as Zheng Fa knows, there are too few cultivators who can die of old age.

Sister Zhang now relies on the Thunder Pond to save her life. Now that the Heavenly Monument has appeared, the Thunder Pond may also have some changes. With the Great Freedom Demon Sect by her side, if the Thunder Pond can no longer protect Sister Zhang, it is questionable whether she can live another nine hundred years.

Even if she can live - the lack of the golden elixir cannot be solved by age.

With Sister Zhang's personality, if she is really sure, she will not answer the question in this way.

"Sister Zhang, I have a guess about the Yin-Yang Yuan Fu..."

At this time, we can only hope that the Yin-Yang Yuan Fu can bring some inspiration to Sister Zhang.

Senior Sister Zhang was also excited, with an expectant look on her face, listening carefully to Zheng Fa's story.

"Chirality?"

"Mirror image?"

After Zheng Fa finished speaking, Senior Sister Zhang closed her eyes and thought for a while, as if simulating in her body.

After a long time, she nodded and shook her head gently, with a hint of disappointment in her calm face.

"I understand chirality." Senior Sister Zhang said to Zheng Fa: "The Yin-Yang Talisman does correspond to the right hand and the left hand."

"But the mirror image... is not very accurate."

Zheng Fa nodded gently, and he also realized this that day:

"Only talking about the five elements of the sub-symbols, the Yin-Yang Talisman is a mirror image of each other, but the talisman is divided into three sub-symbols."

"The other two types of sub-symbols are different in the Yin-Yang Talisman and cannot be regarded as mirror images."

For example, in the Yuan Talisman condensed by Zheng Fa, the Yin-Yang earth-type spiritual talisman is the upright shadowless talisman, and the Yang earth-type spiritual talisman is the awakening talisman.

The only structure that is the same between the two is the earth-type sub-symbol.

The other two types of sub-symbols are completely different.

It is far-fetched to regard them as mirror images.

Senior Sister Zhang nodded slightly, and seeing Zheng Fa's somewhat depressed look on his face, she suddenly smiled and said, "The mirror image theory may not be wrong."

"Well, it's just that I didn't help you."

Zheng Fa whispered.

Last time the theory of the five elements was proposed, Senior Sister Zhang made progress.

Now she seems to have no inspiration.

"No, you're fine." Senior Sister Zhang suddenly said: "Zheng Fa, do you know what I thought of when I named myself a Xuan Guan Jian?"

"What?"

"I'm glad." Senior Sister Zhang said softly, "I'm glad I went to Zhao Mansion that time."

"I'm glad I introduced you to the Nine Mountains Sect."

"I'm glad that I passed on the "Tao Foundation Building Method" to you."

Zheng Fa was stunned when he heard Senior Sister Zhang continue to say:

"That's why I met you, so Jiushan Sect has the most suitable future leader, so the "Fudao Foundation Building Method" has the best successor."

Senior Sister Zhang was particularly talkative today.

Zheng Fa felt a little depressed, but he didn't know what to say.

"Zheng Fa, even Lord Tianhe is dead, how can I escape? But if you really perfect the "Food Dao Foundation Building Method" in the future, the world will know that there was once a person in this Xuanwei world. Zhang Wuyi said softly.

"The thunder pool is dangerous, you two should go back first." Seeing the silence between the two of them, Senior Sister Zhang sighed softly and said: "I am fine in this Xuanguan Jianzhong. Zheng Fa, why don't you go to the Tianbei first and take a look? come over."

"Besides, I also want to practice."

When she said this, her face was unusually calm.

Hearing what she said, Zheng and Fa could only look at each other and leave.

…

The next day.

Senior Sister Zhang was sitting under the entrance mirror practicing, and saw the figures of Zheng Fa and Senior Sister Yuan again from a distance.

"Didn't I ask you two to come less?"

A faint smile flashed across Senior Sister Zhang's lips, and she asked again.

"I'm here to accompany you!" Senior Sister Yuan said in a sticky tone: "Besides, I'm not a thunder magic practitioner. What does the sky monument have to do with me!"

Senior Sister Yuan has always been simple-minded, and probably because of this, she is actually not slow in cultivation.

Senior Sister Zhang shook her head and looked at Zheng Fa standing aside.

Zheng Fa took out several thick books from his storage bag.

There are some titles written on the cover of the book that even Senior Sister Zhang cannot understand.

"High School Mathematics Volume", "Mathematical Analysis", "Topology"...

Zheng Fa saw her somewhat puzzled look and said, "Senior sister, these are some research methods that may be related to runic diagrams. I think they may be of some help to you."

The most helpful thing for studying runic diagrams is definitely topology.

But topology itself requires some prerequisite knowledge.

For example, the most basic point set topology requires the foundation of mathematical analysis - although mathematical analysis is an introductory course in the university mathematics department, it does not seem to require much foundation.

But in fact, you need to understand some basic function knowledge and set theory knowledge.

Zheng Fa's "High School Mathematics Volume" has written some relevant prerequisite knowledge.

Senior Sister Zhang's eyes were bright and she couldn't help but smile.

"Is this similar to your previous secret techniques?"

"It's more essential content." Zheng Fa opened the book and said: "Those before could only be called methods, but now these are the foundation for producing those methods."

Senior Sister Zhang nodded slightly, with great interest on her face.

Even Senior Sister Yuan also came over, with some curiosity on her face.

"First, we need to understand the classification of numbers..."

Zheng Fa opened the book and preached slowly.

…

Two hours later, Zheng Fa had just entered the functional section of high school—Senior Sister Yuan couldn't stand it anymore.

She looked at Zheng Fa's mouth opening and closing in confusion, resistance slowly rising on her face, as if her brain had developed an instinct for self-protection.

"I..." She suddenly said: "I'll go to the sky monument to have a look!"

"..."

Zheng and Fa turned to look at her, and she whispered: "I suddenly felt something in my heart, that monument is destined for me!"

"Senior sister, didn't you say you don't practice thunder?" Zheng Fa asked.

"Who can say clearly about the relationship between heaven and man?" Senior Sister Yuan shouted as she ran: "Senior Sister Zhang, I will accompany you after Junior Brother Zheng finishes speaking!"

Seeing her running away, Zheng Fa and Senior Sister Zhang looked at each other and couldn't help but shake their heads and chuckle.

"Junior sister Yuan really lacks understanding in this aspect, please continue talking!"

Senior Sister Zhang's eyes were filled with genuine excitement, as if what Zheng Fa said not only did not faze her, but also made her find it extremely interesting.

"Okay, let's look at some basic functions first..."

One speaks and the other listens.

After all, the two of them are cultivators, and they lose track of time when they are really enchanted.

Zheng Fa finished "High School Mathematics" and then talked about the second half of "Mathematical Analysis".

He was a little fascinated. He had learned this from Old Man Bai before, but this was the first time he tried to export and explain this knowledge by himself.

There are actually some different experiences.

"Junior Brother Zheng?" Senior Sister Zhang said suddenly.

"Um?"

"Would you like to go to the Sky Monument to see it too?"

"……ah?"

"I suddenly felt something in my heart. This heavenly monument must be destined for you." Senior Sister Zhang pinched her forehead and seemed to have a headache, but her face was full of sincerity.

I have a connection with that thing, do you feel that way?

This sounds even more outrageous than Senior Sister Yuan’s reason for running away.

Seeing the fearful look in Senior Sister Zhang's eyes as she looked at the book in her hand, Zheng Fa understood:

The teaching of this knowledge should not be too much at one time and must be moderate.

For example, Senior Sister Zhang was filled to the brim...