After a comic interlude with de Nanjac ("Ah! You flatter me. You butter me, as they say here."), Sir Robert enters and meets Mrs. Chelevey. Mrs. Cheveley slyly reveals that she knows a man—Baron Arnheim—from Sir Robert's past. She also poses herself against the dreary demands of marriage (the London season, for example, is far too "matrimonial"; Arnheim traveled like Odysseus without the disadvantage of having a Penelope waiting for him, etc.).
Mason then announces Lord Goring, a witty and ironical dandy who, as the stage notes indicate, would be annoyed if considered romantic. Mrs. Cheveley precisely describes him as such upon discovering he is still a bachelor; apparently the two have met before. Mrs. Cheveley and Sir Robert exit, and Goring saunters over to Mabel Chiltern. The two exchange in flirtatious repartee; De Nanjac then kidnaps Mabel to the music room.
After a brief exchange with his father, Goring turns to Lady Basildon and Mrs. Marchmont for a discussion of married life. Bemoaning the unendurable faultlessness of their husbands, Mrs. Marchmont comes to exclaim: "We have married perfect husbands, and we are well punished for it." They then go on to gossip about the scandalous Mrs. Cheveley.
As discussed in the Context, Wilde's later plays both mirror the conventional themes of the Victorian popular stage—such as loyalty, devotion, undying love, duty, respectability, and so on—and undermine them through their brilliantly choreographed banter. The first half of Act I consists almost entirely of this deceptively frivolous party talk.
Wilde's banter is written in witty, epigrammatic repartee. "Wit" is defined here as the quality of speech that consists in apt associations that surprise and delight; the epigram is a brief, pointed, and often antithetical saying that contains an unexpected change of thought or biting comment. The tone of the epigram is often "half-serious," playing on the potential for misunderstanding. Notably, Act I begins by declaring the absence of any serious purpose in the room; one could say that epigrammatic repartee is speech that refuses to speak seriously. Moreover, as this "half-serious" tone is often ironic, such repartee is often speech that the speaker does not speak in earnest either.
Rhetorically, the epigram is usually dependent on a combination of devices: the play between conventionally paired terms, irony, sarcasm, hyperbole, and paradox. Take then, for example, Lord Goring's rejoinder to his father, Lord Caversham, when the latter accuses him of talking about nothing: "I love talking about nothing, father. It is the only thing I know anything about." At one level, Goring's epigram is sarcastic; at another, it is paradoxical, as one cannot know anything about nothing. The epigram also shifts between conventionally valorized terms: whereas most people would hope to have something substantive to talk about, Goring loves to talk about nothing.