Where does the evil in human heart come from? Is it from a history book?

The sentence "Magic is not magic, Tao is not Tao, and good and evil are in people's hearts" comes from Legend of the Sword and the Chivalrous Man 1, which is a dialogue in the game. In this game, Li Xiaoyao and Zhao Linger met a fortune teller in Beijing. This gentleman claimed that he didn't want money, and figured that there were peach blossoms in Li Xiaoyao, and Zhao Linger would suffer, so he was unlucky and didn't give money to fortune tellers. Then meet again in a restaurant in Chang 'an. At this time, give him money for fortune telling, and he will send you the above two sentences, which also implies the ending of the story.

So this sentence is not included in the history books, but a dialogue in the game "Legend of the Sword and the Chivalrous Man 1".