There's no way to see the reputation for the classes as a whole - when the classes are referred to, it's simply a reference to all of the townsfolk in that specific class. For example, when the nobility is mentioned/affected by something, it always refers to Dawn and all other characters in that social class. Since all of them can have very different reputation, there's no way to display any overarching class reputation. So in order to know if taxing a specific social class will be bad for the reputation with that class, you will have to check the reputation of each townsperson in that class. Hope that helps!