“Then came the journey up to London through Birmingham and the Black District, another lesson, which needed much more to be rightly felt. The plunge into darkness lurid with flames; the sense of unknown horror in this weird gloom which then existed nowhere else, and never had existed before, except in volcanic craters; the violent contrast between this dense, smoky, impenetrable darkness, and the soft green charm that one glided into, as one emerged — the revelation of an unknown society of the pit — made a boy uncomfortable, though he had no idea that Karl Marx was standing there waiting for him, and that sooner or later the process of education would have to deal with Karl Marx much more than with Professor Bowen of Harvard College or his Satanic free-trade majesty John Stuart Mill.”

Act III, sc. v.
Tis Pity She's a Whore (1629-33?)

Source: Men Explain Things to Me

[Morgan, Forrest, Shakespeare—the Man, The works of Walter Bagehot, vol. 1, 1891, https://babel.hathitrust.org/cgi/pt?id=njp.32101064786716;view=1up;seq=388, 280 of 255–302]
Shakespeare—the Man (1853)

As quoted in "Space is still the place" by W. Kim Heron in Metro Times (6 June 2007) http://www.metrotimes.com/editorial/story.asp?id=10582
Context: People have a lot more of the unknown than the known in their minds. The unknown is great; it's like the darkness. Nobody made that. It just happens. Light and all that — someone made that; it's written that they did. But nobody made the darkness. My music is about dark tradition. Dark tradition means a lot more about than black tradition. There's a lot of division in what they call black. I'm not into division. I'm into coordination, discipline and tradition.

Letter to Henry Lee (15 May 1826)
1820s

Quote from The Power of Mystery (7 December 1957), a London Observer interview with John Richardson, as quoted in Braque: The Late Works (1997), by John Golding, Introduction, p. 10
unsourced variant translation: I made a great discovery. I don't believe in anything anymore. Objects do not exist for me, except that there is a harmonious relationship among them, and also between them and myself. When one reaches this harmony, one reaches a sort of intellectual void. This was everything becomes possible, everything becomes legitimate, and life is a perpetual revelation. This is true song.
1946 - 1963

31 May 1981 diary entry (pg. 248 of Herzog's book Conquest of the Useless)

O Black and Unknown Bards, st. 1.
Fifty Years and Other Poems (1917)

Source: For Whom the Bell Tolls (1940), Ch. 13