“My mind… It's who I am. I think I'd rather suffer any other injury in the world than have my mind tampered with.”

Source: Riverside Sermons (1958), p. 22

Catherine Earnshaw (Ch. IX).
Source: Wuthering Heights (1847)
Context: I can not express it; but surely you and everybody have a notion that there is, or should be an existence of yours beyond you. What were the use of creation if I were entirely contained here? My great miseries in this world have been Heathcliff's miseries, and I watched and felt each from the beginning; my great thought in living is himself. If all else perished, and he remained, I should still continue to be; and if all else remained, and he were annihilated, the universe would turn to a mighty stranger. I should not seem a part of it. My love for Linton is like the foliage in the woods: time will change it, I'm well aware, as winter changes the trees. My love for Heathcliff resembles the eternal rocks beneath: a source of little visible delight, but necessary. Nelly, I am Heathcliff - he's always, always in my mind - not as a pleasure, any more than I am always a pleasure to myself - but as my own being; so, don't talk of our separation again - it is impracticable.

Source: How to be Lovely‎ (2005), p. 143

Letter to Robert Bridges (18 October 1882)
Letters, etc
Context: I always knew in my heart Walt Whitman’s mind to be more like my own than any other man’s living. As he is a very great scoundrel this is not a pleasant confession.

Cold Mountain Transcendental Poetry
Context: Today I sat before the cliff
Until the mist and rainbows disappeared
I followed the emerald stream
Explored a thousand tiers of green cliffs
In the morning my spirit rests among white clouds
At night a bright moon floats in the sky
I am free of the busy world
There is not a doubt in my heart or a worry to disturb my mind

In Amrita Ghosh, Author in Focus: An Interview with Dalrymple http://www.cerebration.org/dalrymple.html, Cerebration.Org.

Book IV, Ch. 4
My Antonia (1918)