What does this passage explain about people? why mothers favor some children over others

the contrasting sides of human nature

why there is harmony in all things

left- and right-handedness

The conflict between the twins continued, and for some reason their grandmother favored the left-handed twin. The right-handed twin became angry and resentful. He was the truthful twin who always did the right thing. The left-handed twin was deceitful and did everything backward. You could never trust him.

The twins represent the two ways of the world which are in all people. The Indians do not call these good and evil. They call them the straight mind and the crooked mind, the righteous man and the devious man, the right and the left.

—The World on Turtle’s Bac