Two different interpretations of self . We see two linear class hierarchies. The class C inherits from B, which in turn inherits from A. And similarly, F inherits from E, which inherits from D. The one to the left - in the green class hierarchy - is the naive one we have obtained in our templates and examples until now. The one to the right - in the yellow class hierarchy, shows another interpretation of self . Following this interpretation, self at all levels refer to the most specialized object part.