Controllable variables and uncontrollable variables. Cultivators pursued cultivation in the hope of turning uncontrollable variables into variables they could control-in other words, defying Heaven.
The more controllable variables, the better; the fewer uncontrollable variables, the better. Yet even cultivators could not control everything in the end. Instead, they would be assimilated by the Heavenly Dao.
There were too many uncontrollable variables and too few controllable ones.
The human heart was an enormous uncontrollable variable. To control their own hearts, cultivators endured the turmoil of heart demons, and only after Three Corpses Slaying could they barely be considered masters of themselves.
But even after mastering themselves, there were still the hearts of others. Treachery or loyalty could hinge on a single thought. Some cultivators would establish a rule for themselves, setting a reverse scale that must never be touched.
Everything else could change, but that reverse scale could not. Han Li's rule was Nangong Wan. Everything could change, but his first woman could not.
No matter how his surroundings changed, he remained wholeheartedly devoted to Nangong Wan. His feelings would not shift with his circumstances.
The surroundings changed, people's hearts changed, and they themselves changed. All were uncontrollable variables.
Faced with such a vast number of uncontrollable variables, it was hardly surprising that Ling Yuling harbored doubts and questioned herself. Even the Twin Saints would question things.
For instance, because their spiritual roots lacked some of the five elements, not only could they not master the cultivation method they practiced, but they were also restricted by Magnetic Origin Mountain. Cultivators could not even control their own spiritual roots.
A heavenly spiritual root did indeed allow extremely rapid cultivation at first. But the further one progressed, the more necessary it became to unite the five elements. A single spiritual root was no