Raymond calls Meursault at the office and tells him his friend has invited Meursault to his beach house that weekend. When Meursault says he already has plans with Marie, Raymond invites Marie too. Raymond then adds that "he'd been followed all day by a group of Arabs" including his mistress' brother, and asks Meursault to keep an eye out for him.
Did Raymond call to invite Meursault away for the weekend or because he wants Meursault to come along to look out for him? Either way, Raymond's friendship demands favors.
Soon after, Meursault's boss offers Meursault an opportunity to transfer to a position in Paris. When Meursault is indifferent to the offer, the boss is surprised that Meursault doesn't want "a change of life." Meursault replies "that people never change their lives, that in any case one life was as good as another and that I wasn't dissatisfied with mine here at all." Upset, his boss accuses Meursault of lacking ambition. Returning to work, Meursault recalls that he had ambitions as a student but had lost them when he left his studies and realized that nothing mattered.
That evening, Marie asks Meursault if he wants to marry her. He says it makes no difference to him and they can marry if she wants. When she asks if he loves her, he again says "it didn't mean anything" but probably not. Meursault denies that marriage is "a serious thing." When she asks if he would marry a woman with whom he had a similar relationship as the one he had with her, Meursault says, "Sure." Marie debates aloud with herself while Meursault stays silent. Then she smiles and says she wants to marry. Meursault tells her about the Paris job and Marie says "she'd love to see Paris."
Meursault again proves himself incapable of emotional attachment. He insists love is meaningless. Along with contradicting society's general beliefs about love, Meursault's answers contradict Marie's beliefs specifically. Saying he'd marry another woman in the same circumstances insults Marie by implying there is nothing unique about her. Marie is surprisingly tolerant of Meursault's chilliness.
Marie has to go so Meursault eats alone at Céleste's. "A strange little woman" enters and asks to sit with Meursault, who agrees. She orders all her courses at once and counts out the payment in advance, then spends the meal checking off radio programs from a long list for that week. Meursault observes her meticulously, then follows her out of the restaurant for lack of anything better to do. She moves "with incredible speed and assurance" and doesn't turn around. He quickly forgets about her.
The strange little woman is Meursault's opposite, planning out her meal in advance, calculating her activities, and generally conveying the desire for control and the confidence to exert it. Her way of life is in marked contrast to Meursault's passivity, indifference, and unassertiveness. This contrast is emphasized when Meursault follows her for no good reason at all.
Back at home, Salamano tells Meursault that his dog is truly lost or dead because it isn't at the pound. Meursault is a little irritated but not yet tired so he asks Salamano about the dog "just for something to say." Salamano explains that he'd wanted to go into theater as a youth but had ended up working on railroads. He'd been married unhappily but tolerably. After being widowed, he got the dog and raised it tenderly. After the dog got sick, he'd rub the dog daily with skin ointment.
Meursault shows Salamano kindness by inviting him in to talk, but Meursault's internal reasoning calls that kindness into question. He claims to invite Salamano in simply to have some company and asks about the dog because he can't think of what else to say, not because he sympathizes. Salamano's account reveals just how deeply and tenderly he loved the dog.
Meursault apologizes about the dog and Salamano thanks him, saying Mme Meursault had been fond of it and expressing his sympathy for Meursault, who remains silent. Salamano sheepishly admits that, while neighbors think it was cruel to send his mother to the home, Salamano knows Meursault loved her. Meursault replies he didn't realize people thought that way and had sent her way only because it was "the natural thing," he was poor, and she had nothing to say to him. Salamano bids goodnight, saying his life has changed, and shakes Meursault's hand.
Whether or not Meursault's kindness towards Salamano is authentic, Salamano appreciates it. Meursault's surprise at his neighbors' reactions attests to Meursault's ignorance of conventional social expectations. Meursault seems to use "natural" to mean "practical," whereas his neighbors would likely use it to mean "heartfelt" or "familial."