Internal force—both a familiar and unfamiliar term. To Xiang Yang, it represented an indescribable temptation and a lingering knot in his heart, because it simply should not have existed.
With internal force, one could split bluestone with a palm, cross water by stepping on duckweed, or go further still and release saber qi and sword qi. A forty-meter greatsaber was no dream—it was already transcendent might. No mortal could withstand such power, especially not a shut-in from Earth like Xiang Yang.
After taking several deep breaths and calming his excitement, Xiang Yang skipped over the first diagram of the human meridians and internal-force circulation route. He directly picked up the second section, which covered breathing and exhalation, sensing inner breath, and thereby cultivating internal force.
In the path of martial arts, internal force was the foundation. Truly profound and powerful martial arts all required inner cultivation as their base, such as Divine Steps Shifting Form. Likewise, internal force allowed one to achieve twice the result with half the effort in training, as with the Iron Finger Technique.
So where did internal force come from?
According to the Basic Breathing Technique, the human body possessed the three treasures of Essence, Qi, and Spirit. Cultivating martial arts also had to begin from these three aspects.
The Basic Breathing Technique was merely the crudest and simplest method of inner cultivation. It involved only the cultivation of Essence. In Xiang Yang's understanding, this was the stage of refining Essence into Qi, known in martial arts as the Houtian Realm.
Essence was the vital essence that constituted human life, and it could be understood from both innate and acquired perspectives.
Innate Essence was present from birth and lay hidden throughout every part of the human body. It was primordial essence, also called original sexual essence.