When a definition contains a list such as this, the terms within the list must be within the same class.
Who says? Suppose I define the term "mammal" like so:
The term mammal means any animal with warm blood, vertebrae, milk glands (in females), in utero gestation (in females), and fur
If someone said "fur must mean something else because everything else in the list is in the class 'things inside the body'" <-- I would think that's a silly statement
In any list of things, you can always find some principle of distinction by which one of its items isn't in the same class as the others. Therefore not every item in a list has to be in all of the same classes as the others. If this was a requirement, definitions could never contain lists while remaining true.
Who says? Suppose I define the term "mammal" like so:
If someone said "fur must mean something else because everything else in the list is in the class 'things inside the body'" <-- I would think that's a silly statement
In any list of things, you can always find some principle of distinction by which one of its items isn't in the same class as the others. Therefore not every item in a list has to be in all of the same classes as the others. If this was a requirement, definitions could never contain lists while remaining true.