I am studying Obversion for the first time in terms of Venn Diagrams. I'm am struggling to understand the conventions. Obversion requires two steps: (1)The quality must be changed. (2)The predicate is replaced with it's complement. Before I go on, I want to point out two types of statments that create the problem for me in understanding Obversion. There are two ways A, E, I, and O statments can be written. (1)The subject and the predicate are both subjects. (2)The subject and predicate of the statements are a subject and a class. Example A type: (1)Dogs are Humans. (Subject, Subject) (2)Dogs are in the class Human. (Subject, Class) (I consider the copula the determiner of quality and have highlighted it.) Now here is (2) example in the Obverse: (2)Dogs are not in the class non-Human. (Subject, Class) Here's the problem: In the example in my book, the Venn Diagram puts the dogs in the class of humans. Non-Humans is the class containing Dogs. Saying Dogs are not in their own class is all I see the Obverse form saying. How do I see the inference they are in the human class in the Obverse form?