There is no one for spying on people’s actions like those who are not concerned in them.
 Victor Hugo, Les Misérables (1862). copy citation

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Author Victor Hugo
Source Les Misérables
Topic action spy
Date 1862
Language English
Reference
Note Translation by Isabel F. Hapgood in 1887
Weblink http://www.gutenberg.org/files/135/135-h/135-h.htm

Context

“As she only knew how to sign her name, she was obliged to write through a public letter-writer. She wrote often, and this was noticed. It began to be said in an undertone, in the women’s workroom, that Fantine “wrote letters” and that “she had ways about her.” There is no one for spying on people’s actions like those who are not concerned in them. Why does that gentleman never come except at nightfall? Why does Mr. So-and-So never hang his key on its nail on Tuesday? Why does he always take the narrow streets? Why does Madame always descend from her hackney-coach before reaching her house?” source