Julien plans his campaign and, after much anguish, takes Mme. de Rênal's hand the next evening. Although she at first withdraws, he insists, and ultimately, she offers it freely. Rênal offends Julien by accusing him of neglecting the children, but Julien's sullen mood is suddenly changed by the imminence of a catastrophe: Rênal might find his hidden picture of Napoleon as the mayor and the servants change the mattress stuffing. Mme. de Rênal rescues it for Julien, unaware of whose picture the box contains. Rênal, on the other hand, misinterprets Julien's pride for the cunning of the peasant demanding more wages. When he grants Julien a raise, the latter is abashed and scorns the mayor even more for measuring everything in monetary terms. Julien gives expanse to the joy of victory in the solitude of the mountains as he goes to visit Chélan.
The next night, Julien dares to show his scorn of Rênal by taking Mme. de Rênal's hand in his very presence, albeit under the cover of dark, and he covers it with passionate kisses. Julien contemplates his campaign against this contemptible bourgeois; Mme. de Rênal is torn between her jealousy and anguish at the first pangs of guilt, imagining herself to be a fallen woman. Her agitation is so great that she almost betrays her passion by asking Elisa abruptly if it is she, Elisa, whom Julien loves. Mme. de Rênal resolves to treat Julien coldly.
Julien takes offense and does not confide to her his plans to leave for a three-day trip. He stops off again in the mountains to enjoy his freedom in solitude. During their visit, Fouqué offers Julien a partnership that would assure the latter of financial success. After deliberation, Julien rejects the offer since the success he envisages must be gained through hardship and accomplished by means of the Church. His friendship itself is instrumental in his rejection of the offer. He would not choose to betray Fouqué later, once his education had been financed. Fouqué confides to Julien the tales of his amorous conquests.
Upon his return, Julien discovers that Mme. de Rênal is in love with him, and he decides that his duty requires that he make her his mistress. He announces that he must leave since he loves her desperately. This avowal sends her into ecstasy, but she innocently assures herself that their relationship will be a platonic one. Julien awkwardly begins his seduction.
His absence, caused by another trip to Verrières, where he witnesses the disgrace into which Chélan has fallen, causes his awkward attempts of the previous day to be forgotten. He announces quite abruptly to Mme. de Rênal that he will visit her room at two o'clock in the morning. The declaration is met with an indignant reprimand. He forces himself to carry out this, the most daring of his exploits, and it succeeds only because he forgets his plan and throws himself at Mme. de Rênal's feet. He is unable to enjoy the experience, however, since he is so occupied seeing himself in the role of lover. Returning to his room, Julien's only thought is whether he played his role well.
In spite of the obvious earnestness of the characters, the reader cannot help but be amused at the "comedy of errors and cross purposes" that is played out in these chapters, having its climax in Chapter 15 with the seduction of Mme. de Rênal.
This triumph is not due to Julien's art but rather to his charm, which erupts in unguarded moments; to Mme. de Rênal's love for him, which by this time has become passion; and to the unknowing collaboration of the mayor. Stendhal manipulates the episodes in such a way that each of the three characters acts independently of the others, yet almost by chance they contribute by their convergence to the fortuitous victory of Julien.
This unwitting conspiracy is apparent upon analysis. Julien's ambition to seduce Mme. de Rênal does not result from love for her but from his sense of duty toward himself. He owes it to himself to take her hand, but he has forgotten the incident the next morning. To motivate this "de-motivated" campaign, Stendhal then utilizes the mayor, whose reproach to Julien for his idleness provokes the latter to avenge his wounded pride by demanding an apology. To the amazement of Julien, the mayor grants him a raise. Julien realizes, however, that this second victory has not been earned, but the elation of the victories must be expressed in the solitude of the mountains.
Julien's next step is again motivated by his scorn for the mayor. What an expression of ridicule to take Mme. de Rênal's hand in the presence of her husband! That evening, Julien relaxes enough to actually enjoy the unknown pleasure that her beauty causes him. Planning his strategy according to Napoleon, he will further crush the mayor by requesting a three-day leave. Already, in spite of himself, however, a feeling for Mme. de Rênal is autonomously manifesting itself. Stendhal comments that Julien longed to see her again, in spite of his expectations. The mutual coldness of their interview summarizes their dilemma: It moves them apart in order, ultimately, to unite them.
The numerous absences of Julien ripen Mme. de Rênal for the ultimate conquest, although Julien does not absent himself for that specific purpose. The tranquility enjoyed by Julien during his second retreat to the mountains is disturbed by Fouqué's offer. Even this obstacle advances Julien's cause, unbeknownst to him: It frees his mind to think of her. Fouqué's amorous affairs teach Julien something about women. Upon his return, therefore, he comes "naturally" to the realization that Mme. de Rênal loves him. This proves to be the greatest step in his progression since when she herself initiates the hand-clasp ritual, Julien "ups the ante" in his self-imposition of obstacle pattern, deciding that it is his duty to seduce her, to make her his mistress. This decision, then, is made in all lucidity.
With no love yet prompting him, only his ambition and pride, Julien announces hypocritically that he loves her passionately. As he executes his plan, he falls from blunder into blunder, and his attempts at paying court are climaxed by his brutal announcement of the early morning visit he will pay. Had Mme. de Rênal not been moved by Julien's tears of confusion and had her love not progressed to its paroxysm, she would never have given herself. Julien's conquest of Mme. de Rênal and his love for her at this point take the form of a military assault on society.
Mme. de Rênal, on the other hand, already painfully knows the bliss of love. She allies herself unknowingly more and more closely with Julien against her husband. The sweet complicity into which she enters with Julien has a twofold importance: It is a sign of a greater degree of involvement with Julien and a means to the realization of a further step in the crystallization of her love because it contains the seeds of jealousy which will torment her.
At first her conflict is between the fear of not being loved and the shame of becoming an adulteress. Then when she permits herself to enjoy the thought of happiness with Julien, she is tormented by jealousy, by the fear that he loves another. Soon fear of Julien's departure overcomes any thought she has of resisting him. His hypocritical confession of love for her sends her into a blissful state, although she continues to delude herself as to the future of their relationship, which she can only see as platonic.
The final blunder that precipitates the seduction again reproduces in miniature their entire experience. He clumsily tries to make contact with her foot; she reproaches him, ordering him to be careful; he is offended by the tone and leaves for a day, an absence that prepares her to accept him.
In the two studies of love that the novel presents, with Mme. de Rênal, and in Part II, with Mathilde, Stendhal is not only contrasting two types of love — passionate and intellectual — but is focusing different stages of the love experience, and the two are presented in a complementary way. Julien and Mme. de Rênal are united through blunder and by accident, and separation brings about the union. Julien and Mathilde will both calculate, and Julien will succeed in keeping her love alive only through imposing separation and distance.