different between hardheartedness vs callosity

English

hardhearted +? -ness

hardheartedness (countable and uncountable, plural hardheartednesses)

But anyone who takes these as pretext to blame the authorities for their hardheartedness should recall one or two things. - Why we should keep a murderer alive, The Week, Issue 601, page 16.

callosity (countable and uncountable, plural callosities)

(countable) A callus
(uncountable) A callous demeanour; insensitivity or hardheartedness
- 1820, Charles Maturin, Melmoth the Wanderer, volume 1, page 291:
  The repetition of religious duties, without the feeling or spirit of religion, produces an incurable callosity of heart.

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