The three talents of "The Way of the Three Talents" refer to heaven, earth, and people. The Zhouyi points out the relationship between heaven, earth, and people through hexagrams and lines, and guides the words and deeds of gentlemen, and corrects their reputation.
"Six positions form a chapter" should mean that the yin and yang of the six lines of the hexagram alternately change, and the eight hexagrams fluctuate up and down, but there are internal laws, which is called a chapter.
Haha, my own understanding~