Among other common lies, we have the silent lie—the deception which one conveys by simply keeping still and concealing the truth. Many obstinate truth-mongers indulge in this dissipation, imagining that if they speak no lie, they lie not at all.
 Mark Twain, On the Decay of the Art of Lying (1880). copy citation

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Author Mark Twain
Source On the Decay of the Art of Lying
Topic truth self-deception
Date 1880
Language English
Reference
Note
Weblink http://www.gutenberg.org/cache/epub/2572/pg2572-images.html

Context

“The man who tells a lie to help a poor devil out of trouble, is one of whom the angels doubtless say, "Lo, here is an heroic soul who casts his own welfare in jeopardy to succor his neighbor's; let us exalt this magnanimous liar."
An injurious lie is an uncommendable thing; and so, also, and in the same degree, is an injurious truth—a fact that is recognized by the law of libel.
Among other common lies, we have the silent lie—the deception which one conveys by simply keeping still and concealing the truth. Many obstinate truth-mongers indulge in this dissipation, imagining that if they speak no lie, they lie not at all. In that far country where I once lived, there was a lovely spirit, a lady whose impulses were always high and pure, and whose character answered to them. One day I was there at dinner, and remarked, in a general way, that we are all liars.” source