Classificatory disputes about art

Classificatory disputes about art are disagreements about what kind of art something is. For example, some people might think a painting is abstract, while other people might think it's expressionist. It's like arguing about whether a certain thing is a chair or a sofa - both can be used for sitting, but they're actually different things. Similarly, both abstract and expressionist art can be used for expressing ideas, but they're different kinds of art. Sometimes people will disagree about what kind of art something is, and that's called a classificatory dispute.