To act with doubleness towards a man whose own conduct was double, was so near an approach to virtue that it deserved to be called by no meaner name than diplomacy.
Source: Felix Holt, The Radical, ch. 29, 1866.
-- George Eliot, (Nov 22 1819-1880), English novelist; Mary Ann Evans was the foremost woman novelist of her time, e.g., Silas Marner, 1861.