As Lydia reads, Oblonsky is baffled by the whole situation, and he begins to fall asleep. He snaps awake when Lydia says, “He’s asleep,” but she is speaking about Landau, not him. Through his sleep (or feigned sleep), Landau says, in French, that the person who came in last wants something and should leave. Oblonsky, completely perplexed and unnerved, leaves without asking either about his own promotion or about Anna’s divorce. He goes to the French Theatre to adjust back to normal society. The next day, Karenin sends Oblonsky his definitive word that he will not divorce Anna, likely because of something Landau had said in his sleep or fake dream-like trance.
Landau uses the high-society language of French, which demonstrates Tolstoy’s deep skepticism still further: not only is he communicating verbally, always a suspicious prospect, he is communicating in French, the language that people use when they’re pretending to be in high-class society, instead of being true to themselves and using their native tongue. Even Oblonsky, who is usually perfectly at ease in every permutation of social setting, has no idea what to do in this scenario, which demonstrates how deeply unnatural and fake the whole séance is. And yet Karenin is completely under its sway.