the slave is a living tool and the tool a lifeless slave.
 Aristotle, Nicomachean Ethics (c. 334 BC - 330 BC). copy citation

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Author Aristotle
Source Nicomachean Ethics
Topic tool living
Date c. 334 BC - 330 BC
Language English
Reference
Note Translated by W. D. Ross
Weblink http://classics.mit.edu/Aristotle/nicomachaen.mb.txt

Context

“the latter in each case is benefited by that which uses it, but there is no friendship nor justice towards lifeless things. But neither is there friendship towards a horse or an ox, nor to a slave qua slave. For there is nothing common to the two parties; the slave is a living tool and the tool a lifeless slave. Qua slave then, one cannot be friends with him. But qua man one can; for there seems to be some justice between any man and any other who can share in a system of law or be a party to an agreement; therefore there can also be friendship with him in so far as he is a man.” source