Yeah but then neither does the cheese right? There’s no actual unity to objects, even solid objects, just parts interacting circumstantially, and any part can be subdivided into more parts interacting circumstantially.
The unity of the block of cheese is circumstantial, but nonetheless we define a piece of cheese defined on the presence of actual matter. The article goes to some trouble to devise a definition of holes that's also based on matter rather than its absence. But only a strict materialist would feel the need to do that, assuming they didn't want to outright deny existence to holes.
