500
Author of the following quote "It is a peculiar sensation, this double-consciousness, this sense of always looking at one's self through the eyes of others.... One ever feels his twoness—an American, a Negro; two souls, two thoughts, two unreconciled strivings; two warrings ideals in one dark body, whose dogged strength alone keeps it from being torn asunder."
Who is W.E.B. Du Bois?