We should never say anything with an air of authority, nor show any superiority of mind.
 François de La Rochefoucauld, Reflections; or Sentences and Moral Maxims (1665). copy citation

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Author François de La Rochefoucauld
Source Reflections; or Sentences and Moral Maxims
Topic superiority authority
Date 1665
Language English
Reference
Note Translated by J. W. Willis Bund
Weblink http://www.gutenberg.org/files/9105/9105-h/9105-h.htm

Context

“We cannot give too great study to find out the manner and the capacity of those with whom we talk, so as to join in the conversation of those who have more than ourselves without hurting by this preference the wishes or interests of others. Then we should modestly use all the modes abovementioned to show our thoughts to them, and make them, if possible, believe that we take our ideas from them. We should never say anything with an air of authority, nor show any superiority of mind. We should avoid far-fetched expressions, expressions hard or forced, and never let the words be grander than the matter. It is not wrong to retain our opinions if they are reasonable, but we should yield to reason, wherever she appears and from whatever side she comes, she alone should govern our opinions, we should follow her without opposing the opinions of others, and without seeming to ignore what they say.” source