While a man is allowing music to pour like water through the funnel of his ears, the edge of his soul gradually wears away, and the passionate or spirited element is melted out of him. Too little spirit is easily exhausted; too much quickly passes into nervous irritability. So, again, the athlete by feeding and training has his courage doubled, but he soon grows stupid
 Plato, The Republic. copy citation

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

Context

“The two together supply our guardians with their twofold nature. The passionate disposition when it has too much gymnastic is hardened and brutalized, the gentle or philosophic temper which has too much music becomes enervated. While a man is allowing music to pour like water through the funnel of his ears, the edge of his soul gradually wears away, and the passionate or spirited element is melted out of him. Too little spirit is easily exhausted; too much quickly passes into nervous irritability. So, again, the athlete by feeding and training has his courage doubled, but he soon grows stupid; he is like a wild beast, ready to do everything by blows and nothing by counsel or policy. There are two principles in man, reason and passion, and to these, not to the soul and body, the two arts of music and gymnastic correspond.” source