For dogs are gentle to friends and fierce to strangers.
 Plato, The Republic. copy citation

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Author Plato
Source The Republic
Topic strangers dog
Date
Language English
Reference
Note Translated by Benjamin Jowett
Weblink http://www.gutenberg.org/files/1497/1497-h/1497-h.htm

Context

“the union of gentleness to friends and fierceness against enemies appears to be an impossibility, and the guardian of a State requires both qualities. Who then can be a guardian? The image of the dog suggests an answer. For dogs are gentle to friends and fierce to strangers. Your dog is a philosopher who judges by the rule of knowing or not knowing; and philosophy, whether in man or beast, is the parent of gentleness. The human watchdogs must be philosophers or lovers of learning which will make them gentle.” source