Untapped Potential I
Although humans and the other races lived together with spirit beasts in a somewhat peaceful manner. Conflicts would surely arise from time to time. Even if it wasn't explained, Bai Xue already knew of this.
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The idea of everyone coexisting in a peaceful manner where no fights was present was nothing but wishful thinking. Fights and killings cannot be changed, and to those who believed that peace will come, just look at the story that Wang Ling had just told Bai Xue.
If the utopian society of that ancient emperor came into full view. Then it wouldn't have perished and Wang Ling's era wouldn't have risen. In the end, that era was destroyed and replaced.
The idea of utopia was endearing, but it can never come to pass. Why? Because no matter what race or what species you belong in. Only by stepping in the corpses of other people will you rise.