Columbia subject headings:
Harvard subject headings:
Cosmology--Congresses
Physics--Philosophy--Congresses
Plato--Congresses.
Science--Philosophy--Congresses
Princeton subject headings:
Nature--Congresses.
Ontology--Congresses.
Philosophy, Ancient--Congresses.
Physis (The Greek word)--Congresses.
Pre-Socratic philosophers--Congresses.