The main impulse for this considerations is a beautiful Professor Adam Nowaczyk's text "The
spell of Plato. Reflections on Roman Ingarden's ontology".
My general (negative) thesis is that no hyper-dietetic, i.e. monocategorial, ontology (meant
as the theory of real objects) is not correct. Thus neither the theory of sets (if it assumed the
uniqueness of the ontic category of sets), nor reism (if it assumed the uniquenes of the ontic
category of things) or eventism (if it assumed the uniqueness of the ontic category of events) are
correct ontologies (meant as theses on existence of a certain ontic category).
The consequence of this negative thesis is that only non-dietetic, i.e. polycategorial, ontology
can be correct.
I present a few arguments on account of theses two theses.