But when one begins to aspire to pre-eminence, it is difficult to preserve that spirit of fairness which is absolutely essential to justice.
 Marcus Tullius Cicero, On Duties (44 BC). copy citation

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Author Marcus Tullius Cicero
Source On Duties
Topic fairness justice
Date 44 BC
Language English
Reference
Note Translated by Walter Miller
Weblink http://www.constitution.org/rom/de_officiis.htm

Context

“For just as Plato tells us that the whole national character of the Spartans was on fire with passion for victory, so, in the same way, the more notable a man is for his greatness of spirit, the more ambitious he is to be the foremost citizen, or, I should say rather, to be sole ruler. But when one begins to aspire to pre-eminence, it is difficult to preserve that spirit of fairness which is absolutely essential to justice. The result is that such men do not allow themselves to be constrained either by argument or by any public and lawful authority; but they only too often prove to be bribers and agitators in public life, seeking to obtain supreme power and to be superiors through force rather than equals through justice.” source