one can hardly be prejudiced in one’s own cause.
It is not the same with the differences which happen among individuals.
 Montesquieu, Persian Letters (1721). copy citation

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Author Montesquieu
Source Persian Letters
Topic prejudice difference
Date 1721
Language English
Reference
Note Translated by John Davidson
Weblink https://en.wikisource.org/wiki/Persian_Letters

Context

“There is rarely need for a third party to act as umpire between nation and nation, because the subjects in dispute are almost always clearly defined and easily decided. The interests of two nations are usually so distinct, that it is only necessary to love justice to discover where it lies; one can hardly be prejudiced in one’s own cause. It is not the same with the differences which happen among individuals. As they live together, their interests are so intermingled and so confused, and also so various that it is necessary for a third party to clear that which the covetousness of the other two endeavours to obscure.” source