“The doctrine of the cynics is the Ideal reversed, the parody of physical and moral beauty, the crime of mind, the degradation of imagination. I could not take pleasure in it. There was too much enthusiasm within me to permit me to crawl through those sinks of the brain. My nature had wings. The dangers to which I was exposed were above, not below.”

Source: The Shadow of the Wind

Source: Autobiography (1873)

https://archive.org/details/autobiography01mill/page/30/mode/1up pp. 30–31

Variant: I would permit no man, no matter what his colour might be, to narrow and degrade my soul by making me hate him.
Source: 1900s, Up From Slavery (1901), Chapter XI: Making Their Beds Before They Could Lie On Them. This statement was quoted in Charm and Courtesy in Conversation (1904) by Frances Bennett Callaway, p. 153 as "I permit no man to narrow and degrade my soul by making me hate him." It has also often been paraphrased in various other ways: I will permit no man to narrow and degrade my soul by making me hate him. I shall allow no man to belittle my soul by making me hate him. I let no man drag me down so low as to make me hate him.
Source: Up from Slavery

Upon being forced to leave a train car due to his color, as quoted in Up from Slavery (1901), Ch. VI: "Black Race And Red Race, the penalty of telling the truth, of telling the simple truth, in answer to a series of strange questions", by Booker T. Washington

Source: White-Jacket (1850), Ch. 67

Letter to Reverend G. W. Snyder (25 September 1798) http://founders.archives.gov/documents/Washington/06-02-02-0435 thanking him for a copy of Proofs of a Conspiracy against All the Religions and Governments of Europe (1798) by John Robison.
1790s
Context: I have heard much of the nefarious, & dangerous plan, & doctrines of the Illuminati, but never saw the Book until you were pleased to send it to me. The same causes which have prevented my acknowledging the receipt of your letter, have prevented my reading the Book, hitherto; namely — the multiplicity of matters which pressed upon me before, & the debilitated state in which I was left after, a severe fever had been removed. And which allows me to add little more now, than thanks for your kind wishes and favourable sentiments, except to correct an error you have run into, of my Presiding over the English lodges in this Country. The fact is, I preside over none, nor have I been in one more than once or twice, within the last thirty years. I believe notwithstandings, that none of the Lodges in this Country are contaminated with the principles ascribed to the Society of the Illuminati.

Autobiography (1873)
Context: Scott does this still better than Wordsworth, and a very second-rate landscape does it more effectually than any poet. What made Wordsworth's poems a medicine for my state of mind, was that they expressed, not mere outward beauty, but states of feeling, and of thought coloured by feeling, under the excitement of beauty. They seemed to be the very culture of the feelings, which I was in quest of. In them I seemed to draw from a Source of inward joy, of sympathetic and imaginative pleasure, which could be shared in by all human beings; which had no connexion with struggle or imperfection, but would be made richer by every improvement in the physical or social condition of mankind. From them I seemed to learn what would be the perennial sources of happiness, when all the greater evils of life shall have been removed. And I felt myself at once better and happier as I came under their influence.

quote in his letter to brother Theo, from The Hague, The Netherlands in Jan. 1882; as quoted in Vincent van Gogh, Alfred H. Barr; Museum of Modern Art, New York, 1935 https://www.moma.org/documents/moma_catalogue_1996_300061887.pdf, p. 20 (letter 171)
1880s, 1882