The Ontology of Thisness

The paper seeks to give an account of what it is for an individual to instantiate thisness, and how an individual and its thisness are related (where the thisness of an individual x is the property of being identical to x). Such an account is completely lacking in the literature, even among those who defend and make use of thisness. My approach is to seek out a model for the instantiation of thisness by canvassing realist accounts of the substance/attribute relation , and then make appropriate modifications to the most likely candidate in order to accommodate an individual's instantiation of thisness (the accounts cannot be strictly identical for reasons that I explain). I go on to suggest that the model can be appropriately applied in the case of other individuals which might instantiate thisness: for example, persons and events (where these are conceived as fundamental categories of ontology distinct from material substances).