Those unfortunate persons whom nature has formed a good deal below the common level, seem sometimes to rate themselves still more below it than they really are.
 Adam Smith, The Theory of Moral Sentiments (1759). copy citation

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Author Adam Smith
Source The Theory of Moral Sentiments
Topic good
Date 1759
Language English
Reference
Note
Weblink https://en.wikisource.org/wiki/The_Theory_of_Moral_Sentiments

Context

“A man of this character must have been very fortunate in the early choice of his companions, if, in going through the world, he meets always with fair justice, even from those whom, from his own past kindness, he might have some reason to consider as his best friends; and a youth, too unassuming and too unambitious, is frequently followed by an insignificant, complaining, and discontented old age. Those unfortunate persons whom nature has formed a good deal below the common level, seem sometimes to rate themselves still more below it than they really are. This humility appears sometimes to sink them into idiotism. Whoever has taken the trouble to examine idiots with attention, will find that, in many of them, the faculties of the understanding are by no means weaker than in several other people, who, though acknowledged to be dull and stupid, are not, by any body, accounted idiots.” source