whenever any one sees, seeks, and WANTS to see only hunger, sexual instinct, and vanity as the real and only motives of human actions; in short, when any one speaks "badly"—and not even "ill"—of man, then ought the lover of knowledge to hearken attentively and diligently; he ought, in general, to have an open ear wherever there is talk without indignation.
 Friedrich Nietzsche, Beyond Good and Evil (1886). copy citation

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Author Friedrich Nietzsche
Source Beyond Good and Evil
Topic action vanity
Date 1886
Language English
Reference
Note Translated by Helen Zimmern
Weblink http://www.gutenberg.org/files/4363/4363-h/4363-h.htm

Context

“It happens more frequently, as has been hinted, that a scientific head is placed on an ape's body, a fine exceptional understanding in a base soul, an occurrence by no means rare, especially among doctors and moral physiologists. And whenever anyone speaks without bitterness, or rather quite innocently, of man as a belly with two requirements, and a head with one; whenever any one sees, seeks, and WANTS to see only hunger, sexual instinct, and vanity as the real and only motives of human actions; in short, when any one speaks "badly"—and not even "ill"—of man, then ought the lover of knowledge to hearken attentively and diligently; he ought, in general, to have an open ear wherever there is talk without indignation. For the indignant man, and he who perpetually tears and lacerates himself with his own teeth (or, in place of himself, the world, God, or society) , may indeed, morally speaking, stand higher than the laughing and self-satisfied satyr, but in every other sense he is the more ordinary, more indifferent, and less instructive case.” source