“We recognize the fact of the inferiority stamped upon that race of men by the Creator, and from the cradle to the grave, our Government, as a civil institution, marks that inferiority.”

Source: Vestiges of the Natural History of Creation (1844), p. 311
Context: Now, as the inferior animals were all in being before man, there was language upon earth long ere the history of our race commenced. The only additional fact in the history of language, which was produced by our creation, was the rise of a new mode of expression—namely that by sound-signs produced by the vocal organs. In other words, speech was the only novelty in this respect attending the creation of the human race.

Epistles, Decade III, epistle 2. Compare: "And cradles rock us nearer to the tomb./Our birth is nothing but our death begun", Edward Young, Night Thoughts, night v., line 718.

1966, Interview with Alex Haley

Anticipations of the Reaction of Mechanical and Scientific Progress Upon Human Life and Thought http://books.google.com/books?id=OTP8dQHO57UC (1901), The Faith, Morals, and Public Policy of The New Republic, pp. 340–343
Context: Money and credit are as much human contrivances as bicycles, and as liable to expansion and modification as any other sort of prevalent but imperfect machine.
And how will the new republic treat the inferior races? How will it deal with the black? how will it deal with the yellow man? how will it tackle that alleged termite in the civilized woodwork, the Jew? Certainly not as races at all. It will aim to establish, and it will at last, though probably only after a second century has passed, establish a world state with a common language and a common rule. All over the world its roads, its standards, its laws, and its apparatus of control will run. It will, I have said, make the multiplication of those who fall behind a certain standard of social efficiency unpleasant and difficult… The Jew will probably lose much of his particularism, intermarry with Gentiles, and cease to be a physically distinct element in human affairs in a century or so. But much of his moral tradition will, I hope, never die. … And for the rest, those swarms of black, and brown, and dirty-white, and yellow people, who do not come into the new needs of efficiency?
Well, the world is a world, not a charitable institution, and I take it they will have to go. The whole tenor and meaning of the world, as I see it, is that they have to go. So far as they fail to develop sane, vigorous, and distinctive personalities for the great world of the future, it is their portion to die out and disappear.
The world has a greater purpose than happiness; our lives are to serve God's purpose, and that purpose aims not at man as an end, but works through him to greater issues.

1850s, Speech at Chicago (1858)

Kosmos (1845 - 1847)
Context: While we maintain the unity of the human species, we at the same time repel the depressing assumption of superior and inferior races of men. There are nations more susceptible of cultivation, more highly civilized, more enobled by mental cultivation than others, but none in themselves nobler than others. All are in like degree designed for freedom; a freedom which, in the ruder conditions of society, belongs only to the individual, but which, in social states enjoying political institutions, appertains as a right to the whole body of the community.

As quoted in His Brother's Blood: Speeches and Writings, 1838–64 https://books.google.com/books?id=qMEv8DNXVbIC&pg=PA193&lpg=PA193 (2004), edited by William Frederick Moore and Jane Ann Moore, p. 193
1860s, Speech to the U.S. House of Representatives (April 1860)

O’Connell’s Correspondence, Letter No 700, Vol II

Preface; Previous Attempts Miss the Point.
1930s, On the Rocks (1933)
Context: The extermination of what the exterminators call inferior races is as old as history. "Stone dead hath no fellow" said Cromwell when he tried to exterminate the Irish. "The only good nigger is a dead nigger" say the Americans of the Ku-Klux temperament. "Hates any man the thing he would not kill?" said Shylock naively. But we white men, as we absurdly call ourselves in spite of the testimony of our looking glasses, regard all differently colored folk as inferior species. Ladies and gentlemen class rebellious laborers with vermin. The Dominicans, the watchdogs of God, regarded the Albigenses as the enemies of God, just as Torquemada regarded the Jews as the murderers of God. All that is an old story: what we are confronted with now is a growing perception that if we desire a certain type of civilization and culture we must exterminate the sort of people who do not fit into it. There is a difference between the shooting at sight of aboriginal natives in the back blocks of Australia and the massacres of aristocrats in the terror which followed the foreign attacks on the French Revolution. The Australian gunman pots the aboriginal natives to satisfy his personal antipathy to a black man with uncut hair. But nobody in the French Republic had this feeling about Lavoisier, nor can any German Nazi have felt that way about Einstein. Yet Lavoisier was guillotined; and Einstein has had to fly for his life from Germany. It was silly to say that the Republic had no use for chemists; and no Nazi has stultified his party to the extent of saying that the new National Socialist Fascist State in Germany has no use for mathematician-physicists. The proposition is that aristocrats (Lavoisier's class) and Jews (Einstein's race) are unfit to enjoy the privilege of living in a modern society founded on definite principles of social welfare as distinguished from the old promiscuous aggregations crudely policed by chiefs who had no notion of social criticism and no time to invent it.