From the physiological standpoint, everything ugly weakens and depresses man.
 Friedrich Nietzsche, Twilight of the Idols (1889). copy citation

add
Author Friedrich Nietzsche
Source Twilight of the Idols
Topic
Date 1889
Language English
Reference
Note Translated by Anthony M. Ludovici
Weblink https://www.gutenberg.org/files/52263/52263-h/52263-h.htm

Context

“all æsthetic rests on this piece of ingenuousness, it is the first axiom of this science. And now let us straightway add the second to it: nothing is ugly save the [Pg 76] degenerate man,—within these two first principles the realm of æsthetic judgments is confined. From the physiological standpoint, everything ugly weakens and depresses man. It reminds him of decay, danger, impotence; he literally loses strength in its presence. The effect of ugliness may be gauged by the dynamometer. Whenever man's spirits are downcast, it is a sign that he scents the proximity of something "ugly."” source