Ontology cannot be left to the natural sciences, if only because it deals also with hypothetical and fictional objects. It pivots about proto-categorical issues relating to the features of objects of any and all kinds. This brings into its range issues that test the limits of knowledge by asking questions that are inherently unanswerable (for example: "What is an instance of an occurrence that no one ever mentions?"). And it raises issues of norms and values that science (in its usual configuration) does not address.