We are sure to displease when we speak too long and too often of one subject, and when we try to turn the conversation upon subjects that we think more instructive than others, we should enter indifferently upon every subject that is agreeable to others, stopping where they wish, and avoiding all they do not agree with.
 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 conversation subject
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

“It is dangerous to seek to be always the leader of the conversation, and to push a good argument too hard, when we have found one. Civility often hides half its understanding, and when it meets with an opinionated man who defends the bad side, spares him the disgrace of giving way. We are sure to displease when we speak too long and too often of one subject, and when we try to turn the conversation upon subjects that we think more instructive than others, we should enter indifferently upon every subject that is agreeable to others, stopping where they wish, and avoiding all they do not agree with. Every kind of conversation, however witty it may be, is not equally fitted for all clever persons; we should select what is to their taste and suitable to their condition, their sex, their talents, and also choose the time to say it.” source