Columbia subject headings:
Idea (Philosophy)--History--18th century--Congresses.
Idea (Philosophy)--History--19th century--Congresses.
Philosophy--Historiography--Congresses.
Harvard subject headings:
Idea (Philosophy)--History--18th century--Congresses.
Idea (Philosophy)--History--19th century--Congresses.
Philosophy--Historiography--Congresses.
Princeton subject headings:
Idea (Philosophy)--History--18th century--Congresses.
Idea (Philosophy)--History--19th century--Congresses.
Philosophy--Historiography--Congresses.