A vicious person, always affecting the same air of virtue before people whom he is anxious to keep from having any suspicion of his vices, has no register, no gauge at hand from which he may ascertain how far those vices (their continuous growth being imperceptible by himself) have gradually segregated him from the normal ways of life.
 Marcel Proust, Swann's Way (1913). copy citation

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Author Marcel Proust
Source Swann's Way
Topic growth suspicion
Date 1913
Language English
Reference
Note Translated by C. K. Scott Moncrieff
Weblink http://www.gutenberg.org/files/7178/7178-h/7178-h.htm

Context

“But, often enough, the things that he did not know, that he dreaded, now, to learn, it was Odette herself who, spontaneously and without thought of what she did, revealed them to him; for the gap which her vices made between her actual life and the comparatively innocent life which Swann had believed, and often still believed his mistress to lead, was far wider than she knew. A vicious person, always affecting the same air of virtue before people whom he is anxious to keep from having any suspicion of his vices, has no register, no gauge at hand from which he may ascertain how far those vices (their continuous growth being imperceptible by himself) have gradually segregated him from the normal ways of life. In the course of their cohabitation, in Odette's mind, with the memory of those of her actions which she concealed from Swann, her other, her innocuous actions were gradually coloured, infected by these, without her being able to detect anything strange in them, without their causing any explosion in the particular region of herself in which she made them live, but when she related them to Swann, he was overwhelmed by the revelation of the duplicity to which they pointed.” source