Columbia subject headings:
Harvard subject headings:
History--Miscellanea--Congresses.
Social change--Philosophy--Congresses.
Social history--Philosophy--Congresses.
Social problems in art--Philosophy--Congresses.
Social problems--Philosophy--Congresses.
World history--Philosophy--Congresses.
World politics--Philosophy--Congresses.
Princeton subject headings:
Social change--Philosophy--Congresses.
Social history--Philosophy--Congresses.
Social problems--Philosophy--Congresses.
World history--Philosophy--Congresses.