The Republic · Rep. 409a–409b

But with the judge it is otherwise; since he governs mind by mind; he ought not therefore to have been trained among vicious minds, and to have associated with them from youth upwards, and to have gone through the whole calendar of crime, only in order that he may quickly infer the crimes of others as he might their bodily diseases from his own self-consciousness; the honourable mind which is to form a healthy judgment should have had no experience or contamination of evil habits when young. And this is the reason why in youth good men often appear to be simple, and are easily practised upon by the dishonest, because they have no examples of what evil is in their own souls.

Plato · translated by Benjamin Jowett · composite transcription based on the 1888 third edition
Benjamin Jowett, revised third edition (1888), with Stephanus numbering from the 1908 edition; composite transcription, Project Gutenberg #55201
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