Sadness (n.) felt in weeping includes the sensations around the eyes, as anger in a frown includes the tension in the forehead.
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Sadness (n.) is learnt from faces in a way similar to, but not quite the same as, 'round' or 'red'; we also react differently to a face's sadness and its redness.
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Sadness (n.) known in someone tells what to expect of him; knowing what will cheer him is a different kind of knowing.
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Sadness (n.) may follow a gland's secretion, but that does not make it a sensation produced by it.
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Sadness (n.) shown in all circumstances would no longer be sadness; a man always looking and acting sad has words that lost their sense.
More Ludwig Wittgenstein
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