“It considers not only how we relate to others, but how we relate to our ideas of others — so that a completely phony, non-human replica of a dead wife can inspire the same feelings that the wife herself once did. That is a peculiarity of humans: We feel the same emotions for our ideas as we do for the real world, which is why we can cry while reading a book, or fall in love with movie stars. Our idea of humanity bewitches us, while humanity itself stays safely sealed away into its billions of separate containers, or "people."”

Kilgore Trout's epitaph
Unsourced paraphrase or variant: We are human only to the extent that our ideas remain humane.
Breakfast of Champions (1973)

"Fala Chen Is Bringing Her Excellence to Hollywood" in Town & Country https://www.townandcountrymag.com/leisure/arts-and-culture/a37223279/fala-chen-jiang-li-shang-chi-marvel-interview/ (1 September 2021)

As quoted in his obituary, Daily Telegraph (4 November 2009) http://www.telegraph.co.uk/news/obituaries/science-obituaries/6496558/Claude-Levi-Strauss.html
Context: The idea behind structuralism is that there are things we may not know but we can learn how they are related to each other. This has been used by science since it existed and can be extended to a few other studies — linguistics and mythology — but certainly not to everything.
The great speculative structures are made to be broken. There is not one of them that can hope to last more than a few decades, or at most a century or two.

Source: Who Is Man? (1965), Ch. 5

Paedagogus 2 (circa 210).

Source: The Other America (1962), p. 170

The Saviors of God (1923)
Context: We do not struggle for ourselves, nor for our race, not even for humanity.
We do not struggle for Earth, nor for ideas. All these are the precious yet provisional stairs of our ascending God, and they crumble away as soon as he steps upon them in his ascent.
In the smallest lightning flash of our lives, we feel all of God treading upon us, and suddenly we understand: if we all desire it intensely, if we organize all the visible and invisible powers of earth and fling them upward, if we all battle together like fellow combatants eternally vigilant — then the Universe might possibly be saved.
It is not God who will save us — it is we who will save God, by battling, by creating, and by transmuting matter into spirit.

Catarina Loss, to Magnus Bane and Ragnor Fell in 1890, p. 42.
The Bane Chronicles, What Really Happened in Peru (2013)

"The Farmer as a Conservationist" [1939]; Published in The River of the Mother of God and Other Essays by Aldo Leopold, Susan L. Flader and J. Baird Callicott (eds.) 1991, p. 259.
1930s