"Races and varieties of the human family appear and disappear, but humanity remains and will remain forever... [P]eople will one day be truer to this idea than now, and will say with Scotia's inspired son, 'A man's a man for a’ that.' When that day shall come, they will not pervert and sin against the verity of language as they now do by calling a man of mixed blood, a negro; they will tell the truth... It is only prejudice against the negro which calls every one, however nearly connected with the white race, and however remotely connected with the negro race, a negro. The motive is not a desire to elevate the negro, but to humiliate and degrade those of mixed blood; not a desire to bring the negro up, but to cast the mulatto and the quadroon down by forcing him below an arbitrary and hated color line."
January 1, 1970
https://en.wikiquote.org/wiki/Race_(human_categorisation)