Columbia subject headings:
Metaphysics--Congresses.
Semantics (Philosophy)--Congresses.
Semiotics--Congresses.
Signs and symbols--Philosophy--Congresses.
Symbolism--Philosophy--Congresses.
Harvard subject headings:
Epistemics.
Knowledge, Theory of.
Princeton subject headings:
Metaphysics--Congresses.
Semantics (Philosophy)--Congresses.
Semiotics--Congresses.
Signs and symbols--Philosophy--Congresses.
Symbolism--Philosophy--Congresses.