The conflict between the right-handed brother and left-handed brother described in"The World on Turtle's Back" shows that the Iroquois most likely believed

The two brothers represent opposing forces: the right-handed brother creates helpful things, while the left-handed brother creates harmful ones. Their conflict suggests that good and evil are in constant opposition, not that real left-handed people are evil or should be treated differently. So the best answer is “there is an eternal battle between good and evil.”

AI-written and checked against the verified answer.