Two may live together without full trust in their hearts if only their past holds no memories of complete and unclouded love; but for those who once have known that intimate life, it becomes intolerable to keep perpetual watch over looks and words.
 Honoré de Balzac, Lost Illusions (1843). copy citation

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Author Honoré de Balzac
Source Lost Illusions
Topic memory past
Date 1843
Language English
Reference
Note Translated by Ellen Marriage
Weblink https://www.gutenberg.org/cache/epub/13159/pg13159.html

Context

“Scoundrels can draw knives on each other and make it up again afterwards, while a look or a word is enough to sunder two lovers for ever. In the recollection of an almost perfect life of heart and heart lies the secret of many an estrangement that none can explain. Two may live together without full trust in their hearts if only their past holds no memories of complete and unclouded love; but for those who once have known that intimate life, it becomes intolerable to keep perpetual watch over looks and words. Great poets know this; Paul and Virginie die before youth is over; can we think of Paul and Virginie estranged? Let us know that, to the honor of Lucien and Eve, the grave injury done was not the source of the pain;” source