Several problems in philosophy of physics have led to ‘ontic structural realism’, i. e., the supposition that, at the fundamental physical level, there are no ‘objects’, but ‘structures’. There are various requirements that a ‘structure’ should satisfy for ‘ontic structural realism’. Structures must be concrete entities, there must be something that fulfills the role of ‘node’, and the relations of the structure must not be dependent on the objects that are being related. Most of the traditional ontologies, both of substrata and properties, and of bundles of properties, seem to be inadequate to satisfy those requirements. It is argued here that there are several ways in which those requirements can be met: by nodal relations, by primitive ‘nodal facts’, and by symmetric dependencies between objects and relations.
Ontic Structural Realism; Structures; Relations; Trope Bundles; Substrata