Whenever she saw in others an advantage, however trivial, which she herself lacked, she would persuade… — Marcel Proust
Whenever she saw in others an advantage, however trivial, which she herself lacked, she would persuade herself that it was no advantage at all, but a drawback, and would pity so as not to have to envy them.
p. 24Source: Wikiquote · CC BY-SA 4.0

