Back at home, Itachi placed Sasuke on the bed, told him to get some proper rest, and then left the room.
But Sasuke didn't want to rest. He knew he wouldn't be able to sleep unless he solved the chakra problem. Sitting up, Sasuke began to recover his chakra. After a while, he realized that once his chakra was fully restored, continuing to gather more had no effect at all. It seemed Itachi was right.
The chakra gathering point is the Chakra Pathway System. Everyone's Chakra Pathway System is a different size, but you can't tell just by looking at someone. Through the Byakugan, it appears that everyone's Chakra Pathway System is about the size of a tennis ball, but their internal structures are all different.
The first time Sasuke focused and gathered chakra, the inside of his Chakra Pathway System felt no larger than a ping pong ball. Slowly, as his ability and age increased, the internal space of his Chakra Pathway System grew larger as well.
Once the Chakra Pathway System was filled to capacity, no matter how much more chakra he tried to gather, it wouldn't increase; the excess chakra would only serve to temper the body.
The original story also proved just how tough ninja bodies are. Like when Iruka blocked that enormous windmill shuriken thrown by Mizuki—he shielded himself with his back, and it sank in only a little. It's clear how incredibly tough a ninja's body can be.
No matter how much chakra he gathered, Sasuke found it would not increase, so he gave up trying to force it.
'Is there really no way?' Sasuke felt a tinge of despair.
Sitting in his room, Sasuke racked his brain. Would he really have to study the Eight Gates technique just to raise his chakra? Deep down, he really didn't want to go down that path. The Eight Gates weren't only hard to train, but also took too much time. Plus, the Eight Gates weren't really all that overwhelming: when Guy fought Kisame, he had to open up to the seventh gate just to defeat him, and then lost the ability to fight. And Sasuke knew the kind of opponent he'd face in the future would be at Tobi's level. The Eight Gates wouldn't be particularly useful then. Unless he absolutely had no choice, Sasuke was determined to avoid learning the Eight Gates.
Sasuke mainly intended to focus his efforts on ninjutsu and genjutsu. As long as his taijutsu wasn't too weak—roughly at Kakashi's level—he figured he'd be fine.
Just thinking of Tobi put Sasuke in a foul mood. Even though, in the original story, Tobi hadn't shown any hostility toward him yet, Sasuke was convinced Tobi had designs on him. Otherwise, he wouldn't have manipulated so much from the shadows. Was it all for the sake of Sasuke's future Eternal Mangekyo Sharingan? Sasuke conjectured darkly. All he really wanted was to live a free and unburdened life, but people like Danzo, Orochimaru, and Tobi simply wouldn't let him be. Well, if they wouldn't let him live in peace, then he would take their lives in return. Sasuke burned with quiet hatred.
"Sasuke, what are you doing? Come out, it's time for dinner."
Mikoto Uchiha's voice called from outside the door. The sound snapped Sasuke out of his thoughts. He rubbed his disheveled hair, not even sure how many times he'd yanked at it during the afternoon, yet he still hadn't come up with a good solution.
Slowly Sasuke got down from the bed and made his way to the door, grumbling inwardly: "If I still haven't figured something out by tonight, then I'll just start on the Eight Gates technique—even if it's tough and might become a burden later, at least it's some kind of solution and could be really useful right now."
Sasuke sat down at the table, looking exhausted. He glanced about; as usual, Itachi and Mikoto Uchiha were the only others there. As for Fugaku Uchiha, he was away at least ninety percent of the time, always in the patriarch's office with the elders, plotting who knew what. In the Uchiha clan, Sasuke only felt close to Itachi and Mikoto Uchiha. Everyone else, including Fugaku Uchiha, was practically a stranger.
"Sasuke, what's wrong? Why do you look so tired? Itachi, what did you do with your brother this morning to get him so worn out?"
Mikoto first turned to Sasuke with concern, then turned and questioned Itachi.
"Mother, today I taught Sasuke ninjutsu. That's why he's this tired."
Itachi looked apologetic.
"Sasuke is only three—how could you teach him ninjutsu so soon?" Mikoto's tone was full of concern despite her chiding.
"Mother, it was my own request. It's not Itachi's fault," Sasuke interjected quickly, not wanting Itachi to take the blame for him.
"Sasuke, you're only three—no need to hurry. You'll learn all this when you start ninja academy at six. No need to train so hard right now."
Mikoto was simply too protective to scold him, and her voice grew gentle.
"Yes, Mother, I'll pay more attention from now on,"
Sasuke answered, though it wasn't exactly what he felt. It was just hard to refuse her kindness.
"Here, Sasuke, have some chicken soup. It'll do you good."
Mikoto ladled a bowl of chicken soup for Sasuke.
"Oh,"
Sasuke took the bowl. On the surface, a few green slices of scallion and a golden layer of chicken fat floated, making it look delicious. He swirled the bowl and watched wisps of white steam drifting upward, showing just how hot the soup was.
Chicken soup, steam… chicken soup, steam… water, steam… water vapor… liquid, gas…
As Sasuke stared into the bowl, his thoughts wandered, following the rising vapor from the soup. And then, it clicked. Sasuke shouted in his mind, "I get it!" Without a second thought for the soup, he gulped it down hastily—only to find it was scalding hot—and rushed off toward his bedroom, breath hissing between his lips.
"Sasuke, what on earth are you— That child! Always so mysterious," Mikoto grumbled, half laughing and half scolding, when Sasuke raced from the table before she could finish her question. Itachi glanced at Sasuke's door and couldn't help but smile to himself.
Back in his room, Sasuke found three sheets of paper and wrote on them: "gas," "liquid," and "solid."
He picked up the one that said "gas" and thought, "If I compare chakra to water vapor, isn't it possible that when chakra reaches a certain density it could condense just like steam? If that's true, then I'll never have to worry about chakra again. Imagine three containers of equal volume, one filled with gas, one with liquid, and one with solid—which is heavier? Of course, the solid weighs the most, the liquid is next, and the gas the least. If you can't change the size of the container, the only way to increase the amount inside is…"
"If I compress my chakra from gas into liquid, wouldn't my reserves instantly multiply several times? And if I managed to condense it to solid, wouldn't it multiply again? My total chakra would be more than ten times what it is now."
Sasuke's imagination ran wild. Just thinking about multiplying his chakra tenfold made him immediately try compressing his chakra.