“Indifference to fate which, though it often makes a villain of a man, is the basis of his sublimity when it does not.”

Affurisms. From Josh Billings: His Sayings (1865)

1790s, The Age of Reason, Part II (1795), The Old Testament

"Man, Androids and Machine" (1975), reprinted in The Shifting Realities of Philip K. Dick (1995) Lawrence Sutin, ed.
Context: These creatures are among us, although morphologically they do not differ from us; we must not posit a difference of essence, but a difference of behavior. In my science fiction I write about about them constantly. Sometimes they themselves do not know they are androids. Like Rachel Rosen, they can be pretty but somehow lack something; or, like Pris in We Can Build You, they can be absolutely born of a human womb and even design androids — the Abraham Lincoln one in that book — and themselves be without warmth; they then fall within the clinical entity "schizoid," which means lacking proper feeling. I am sure we mean the same thing here, with the emphasis on the word "thing." A human being without the proper empathy or feeling is the same as an android built so as to lack it, either by design or mistake. We mean, basically, someone who does not care about the fate which his fellow living creatures fall victim to; he stands detached, a spectator, acting out by his indifference John Donne's theorem that "No man is an island," but giving that theorem a twist: that which is a mental and a moral island is not a man.

Rex v. Inhabitants of Burton-Bradstock (1765), Burrow (Settlement Cases), 535.

Source: Meditations in Wall Street (1940), p. 109

Part II, Chapter III
Les voix du silence [Voices of Silence] (1951)

Source: A Field Guide to Getting Lost

Hyperion http://www.gutenberg.org/etext/5436, Bk. III, Ch. IV (1839).
Variant: Believe me, every heart has its secret sorrows, which the world knows not, and oftentimes we call a man cold, when he is only sad.
Context: "Ah! this beautiful world!" said Flemming, with a smile. "Indeed, I know not what to think of it. Sometimes it is all gladness and sunshine, and Heaven itself lies not far off. And then it changes suddenly; and is dark and sorrowful, and clouds shut out the sky. In the lives of the saddest of us, there are bright days like this, when we feel as if we could take the great world in our arms and kiss it. Then come the gloomy hours, when the fire will neither burn on our hearths nor in our hearts; and all without and within is dismal, cold, and dark. Believe me, every heart has its secret sorrows, which the world knows not, and oftentimes we call a man cold, when he is only sad."

Source: Endymion (1996), Chapter 34 (p. 344)