Jem says there are four kinds of folk, but scout says there is one kind. which view is more accurate? how does it relate to the theme of the book?

I think the topic of the both of them relates on what is the point or the theme of the book. Jem says that there are four kinds of folks, this one refers to the category of all the characters in the book and what Scout says refers the origin of every kind of characters that is in the book. Both of them correlates with each other.