The Nun, by Denis Diderot is the only novel of the eighteenth century that deals with lesbianism in a serious manner. It was written in the 1760's, yet was not published until 1796. The novel especially aroused controversy within religious circles which claimed that the book mocked Catholicism and presented a false image of nuns.
The novel is about a young girl, Susan, who searches for a convent to join. She joins, where she is seduced by the Mother Superior. The plot centres around the physical seduction of Susan by the Superior, yet is complicated by Susan's inherent innocence. She never realises the implications of the sexual acts that she takes part in, and therefore, much to the Superior's frustration, her mind retains its purity. For, in the eighteenth century, a sin could not be labeled as such unless the sinner realised the sinful qualities of their actions, within their own mind.
In other words, it did not actually matter what was physically done, but rather what was thought. Therefore, although there is a physical sexual relationship between the two females within the novel, Susan has not sinned as long as her mind stays pure. The Superior can only be successful in her seduction if she gets Susan to realise her lesbian knowledge' and feel shame for it.
The first night that Susan arrives at the convent, her Mother Superior undresses her and touches her in a s__Sexual manner.__ Susan maintains her innocence by referring to the incident as having a little embarrassed me, I know not wherefore, for neither she nor I meant anything. Susan seems to realise that there is something a little strange about the incident by realising her embarrassment, yet she immediately dismisses either of them from having committed any type of wrongdoing by claiming that their actions did not hold any substantial meaning.
As the reader goes on, he encounters several more 'pure lesbian' interactions between the two women. In a later scene, as Susan plays the harpsichord, the Superior presses against her, and moans with seemingly sexual pleasure. Susan feels that the Superior has simply enjoyed the music immensely. Another scene describes the Mother Superior as she strips Susan, kisses her bosoms, and squeezes her until she has an orgasm. Susan is vaguely affected. She attributes the fact that she is suddenly sleepy in the middle of the afternoon to the possibility that she has caught a disease from the Superior.
It seems that Susan has finally realised her sin. When she is asked by another sister what she and Mother Superior have been doing all afternoon, she admits that I was a little embarrassed by the question. Yet she quickly forgets that the event ever happened.