"Sensei, how do the hand signs work? Why do specific movements with the hands make chakra move in particular ways?"

'I was sure that he wouldn't ask typical questions…' Kakashi thought.

"By gathering chakra and performing hand signs, you make the chakra points in your hands work in a specific pattern. The most common theory is that the chakra points in our hands are special and work like a commanding center by giving instructions to the chakra and the rest of the chakra points. In theory, with perfected chakra control, you can manage to perform every technique without hand signs."

"So, hand signs are like an assisting tool?"

"Exactly. Even though I told you that in theory you can do everything with chakra control, some techniques like the elemental dragon series require more than 40 hand signs. It is almost impossible to perform something like this without assistance."

Sasuke immediately thought of his next question.

"Who created the hand signs? The creator's level of understanding towards the nature of chakra must have been unfathomable."

"Indeed, we can't even comprehend the level of his power. However, we are not really sure about his identity because the information was lost in history. We know some legends about the Sage of Six Paths, who was a godlike figure and is considered the ancestor of all shinobi. Many researchers believe that he was the one who invented them, but we don't have sufficient information to make conclusions."

'So, there was a godlike figure in this world. That's very interesting. I need to find more information about this sage. His life may show me the way towards true power,' Sasuke thought and asked his next question.

"What's the relationship between chakra and intent? For example, when we perform the transformation jutsu, how is our will to transform into a specific form connected with the chakra?"

'It seems that he won't make it easy for me…' Kakashi thought and replied, "I am not really sure. One theory is that one of the chakra points in our brain has the ability to connect with thoughts and imagination."

'Theories without proof again…' Sasuke thought.

"I had the same idea, sensei, but it feels unnatural. 

The transformation jutsu is one of the simplest jutsu and requires only 3 hand signs: Dog-Boar-Ram. But how does it fit so many instructions in only 3 signs? 

You basically tell your chakra to go and read a specific image from your mind and then to create a chakra layer around you which takes the shape of this image. And it is not like these signs are exclusive to this technique. 

How can they possibly contain so much information?"

Kakashi was thoughtful and it took a few seconds for him to reply.

"Sasuke, the truth is that we know too little and I can only theorize about this. I don't think that the instructions work like that. We should also take into account the nature of chakra. 

We know that chakra is made when two types of energies are combined, yin and yang. Yang is the physical energy from the cells and Yin is spiritual energy. 

Yin is used exclusively for techniques like genjutsu where you create scenarios out of your imagination. You basically create something with your chakra that didn't exist before. 

So maybe the instructions for transformation jutsu don't literally describe every step but it may tell your body something like – use the yin part of chakra and create a layer - and then maybe it is the properties of the yin chakra that takes care of the rest."

Sasuke was thoughtful and said, "You said before that you believe that it is one of the chakra points in the brain that connects with thoughts and imagination, and now you said that it is the yin chakra which takes care of that. How do the two of them connect to each other?"

Kakashi was a little troubled and took his time to reply.

"Sasuke, you have to understand that there are several different schools of thought about ninjutsu. 

There is a school of thought which believes that chakra points are like mini brains and they do all the important operations. In this school of thought, the chakra is just a higher form of energy. 

There is a second school of thought that believes that chakra, with its extraordinary properties, is doing most of the work and chakra points are just cells specialized to transform the chakra from one form to another. However, I know a technique that contradicts that, and I believe that this is not the case. 

There is another school of thought which believes that the truth is somewhere between. I believe that this makes the most sense. 

However, most of our knowledge is based on theories and speculations, and we cannot prove it."

Sasuke was a little disappointed. 'The knowledge of this world is a complete mess. There are too many speculations and it seems that nobody knows for sure… My plan to abuse Neji and Naruto to decipher fuinjutsu is more crucial than I thought. It seems that it will also help me develop my own theory about the nature of chakra and ninjutsu.' Sasuke thought.

"Sensei, considering that the Byakugan can see the chakra points, shouldn't we know more about them?"

Kakashi put his right hand on his chin and said, "Sasuke, you have to understand that Konoha was created almost 60 years ago. Before the creation of the village, the clans were in constant wars with each other. Even after the creation of the village, we had 3 great ninja wars. The clans were constantly trying to focus on their combat power, and they didn't have the luxury to study about the nature of chakra. Also, the Hyugas aren't exactly men of science. Most of them are obsessed with their Gentle Fist, and they don't even focus on ninjutsu. Most importantly, even if they knew more about chakra points, they wouldn't have shared it with the rest of the world."

Sasuke nodded in understanding, but his thoughts were different. 'Hyugas are really abominations. To have such a gift and waste it like that…' 

He decided to ignore his thoughts for now and continued, "I also want to ask you about kekkei genkai. What exactly is Sharingan and Byakugan? Are they just mutated DNA?"

"Yes, and in most cases, they are beyond our understanding, and we cannot replicate them. Unfortunately, my knowledge is limited in this field, and I can't tell you much."

'It seems that most of the shinobi are ignorant where it matters. It also seems that there is no such thing as a scientific community… It makes sense considering the state of the world… However, that also means that I need to get my hands dirty to discover the true knowledge.' Sasuke thought.

He noticed that Kakashi had a little discomfort in his expression and wasn't replying easily to his questions. However, he chose to ignore him and continued.

"Considering that we don't understand how hand signs exactly operate, how are shinobi able to keep developing new techniques? I created Oni Dekopin by using chakra control, but what if I wanted to create it by using hand signs?"

Kakashi was happier with this question.

"That's a question that I can answer. I have created my own lightning jutsu when I was 11 years old. However, I had something that you lack right now. I had already studied many different jutsu. 

When you will study the jutsu that you received yesterday, you will start to notice patterns. For example, you will notice that the tiger sign mostly appears in Fire and Earth jutsu, the snake appears in Earth and Lightning jutsu, and the same for many other signs. 

When I created my technique, my lightning affinity was less trained than yours, but it was still very high. With my experience with hand signs in combination with my high lightning affinity, I could gradually understand the sequence of signs that I needed to follow to achieve the technique that I had in mind. Of course, the procedure requires a lot of trial and error, and it can be extremely dangerous if you use your chakra in unnatural ways."

Sasuke was a disappointed with the answers that he received. In the end, all the important questions remained unanswered, and even in his simplest question, the answer was not satisfactory. He didn't have any more important questions and he decided to confirm a suspicion of his.

"Sensei, the jutsu that you used during our spar was suspicious. Did you use jutsu from all the five elements to help me train in them?"

Kakashi nodded, pleased. "Yes, I was sure that you would notice it. I watched your training at the waterfall, and you were trying to affect the leaf with the water, wind, and earth elements. This should have been the second step in your training for elements that aren't your affinity. You are so good with fire because of your training with the Great Fireball Jutsu. It is the same process. 

Choose one of the jutsu that you copied from me. Let's say the water bullet. Use all your chakra and energy to practice this jutsu until you get a good feeling about how the transformation to water feels. Only when you grasp that feeling you should proceed to the next step. 

However, I have to warn you that the more elements you get, the more difficult the process will be because your chakra will be even more resistant to new changes. Also, mastering the element which is strong against your affinity is extremely difficult. In our case, it is wind. 

It is a requirement for jonin to be able to use at least 2 elements. However, most of them stop at this point because of the high difficulty. However, you and I have the advantage of the Sharingan. I am sure that right now you can perform the water bullet even if you can only produce a few droplets of water. This is a very big advantage that can speed up the progress. Normal ninjas have to spend a great amount of effort and time to learn this step and many find it impossible."

Sasuke had no more questions and began his training under Kakashi's watch. He created 11 clones and began practicing the Wind Release: Great Breakthrough. 

Kakashi said that wind would be the most difficult element for him, but he also said that the more elements you master, the more difficult it is to progress. It would be a terrible idea to leave the wind last and make it even more difficult.

Sasuke wanted to practice the Gale Palm instead of Great Breakthrough because it seemed like a very simple and practical technique. However, he rejected the scenario to avoid making Naruto upset.

After about an hour, Kakashi called the team together and started lecturing them about missions and scenarios that might occur. He made them face hypothetical situations and follow specific patterns. He also started teaching them about attacking and defensive team maneuvers.

Before the end of the training, they took part in light spars against him where they weren't allowed to use parts of their move set. Kakashi was a little paranoid about their safety and he wanted to prepare them for all the possible scenarios that might occur in battle.

All in all, it was a productive day for Team 7.

However, Hiruzen, who had been watching his crystal ball since morning, had a terrible expression.

'The questions that he asked are very similar… Did I really make the right choice by giving him back the scrolls? Kakashi, let's hope that you are right.'

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Hello dear readers.

This chapter was difficult to write but I think that it was necessary.

Please comment and tell me your opinion so far!