The privilege of the physical and the status of ontological debates

Theodore Sider in his latest book provides a defense of the substantivity of the first-order ontological debates against recent deflationary attacks. He articulates and defends several realist theses: (a) nature has an objective structure, (b) there is an objectively privileged language to describe the structure, and (c) ontological debates are substantive. Sider’s defense of metaontological realism, (c), crucially depends on his realism about fundamental languages, (b). I argue that (b) is wrong. As a result, Sider’s metaontological realism fails to establish the substantivity of certain ontological disputes. Nonetheless, I will argue denying metaontological realism does not require giving up on the realism about structure, (a), that most of us would like to preserve: namely the idea that there are objective similarities and differences in the world that we try to wrap our minds around.