Every art or science has an interest, but this interest is to be distinguished from the accidental interest of the artist, and is only concerned with the good of the things or persons which come under the art.
 Plato, The Republic. copy citation

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

Context

“In what follows Thrasymachus does in fact withdraw his admission that the ruler may make a mistake, for he affirms that the ruler as a ruler is infallible. Socrates is quite ready to accept the new position, which he equally turns against Thrasymachus by the help of the analogy of the arts. Every art or science has an interest, but this interest is to be distinguished from the accidental interest of the artist, and is only concerned with the good of the things or persons which come under the art. And justice has an interest which is the interest not of the ruler or judge, but of those who come under his sway. Thrasymachus is on the brink of the inevitable conclusion, when he makes a bold diversion.” source