Of course I lie to people. But I lie altruistically — for our mutual good. The lie is the basic building block of good manners. That may seem mildly shocking to a moralist — but then what isn’t?
Quentin Crisp (1908-1999) English writer and raconteur [b. Denis Pratt] Manners from Heaven: A Divine Guide to Good Behavior (1984)
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A Man that should call everything by its right Name, would hardly pass the Streets without being knock’d down as a common Enemy.
George Savile, Marquis of Halifax (1633-1695) English politician and essayist
“Of Caution and Suspicion,” Political, Moral and Miscellaneous Thoughts and Reflections (1750)
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When the issue is one of Truth and Justice, there can be no differentiating between small problems and great ones. For the general viewpoints on human behaviour are indivisible. People who fail to regard the truth seriously in small matters, cannot be trusted in matters that are great.
[Wenn es sich um Wahrheit und Gerechtigkeit handelt, gibt es nicht die Unterscheidung zwischen kleinen und grossen Problemen. Denn die allgemeinen Gesichtspunkte, die das Handeln der Menschen betreffen, sind unteilbar. Wer es in kleinen Dingen mit der Wahrheit nicht ernst nimmt, dem kann man auch in grossen Dingen nicht vertrauen …]
Albert Einstein (1879-1955) German-American physicist
“Albert Einstein on Israeli-Arab Relations,” New Outlook (Jul 1957)
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Often paraphrased / translated, "Anyone who doesn't take truth seriously in small matters cannot be trusted in large ones either." See here for more discussion.