Sonya and Yelena now enter the garden. Momentarily Maria Vasilevna also joins the party and begins to read a book. Sonya informs the nurse that some men have arrived from the village and asks her to attend to them: Marina exits.

Idle conversation ensues. Astrov has rushed to the estate to treat Professor Serebryakov's gout and rheumatism only to discover that Serebryakov is doing fine. Exhausted from his trip, the doctor will now join the group for dinner and spend the night. Sonya discovers the tea is cold, the samovar having been out since the morning (again, note the petty details). When Yelena mispronounces Telegin's name, the latter peevishly reproaches her, reminding her of his long history with the estate ("Nowadays I live here, ma'am, on this estate, ma'am You may have been so good as to notice I eat dinner with you every day"). Maria abruptly exclaims that she forgot to tell the professor of an "awful" pamphlet she received, in which the author refutes a point he defended seven years ago. Voynitsky dismisses his mother's chitchat, and she protests, "But I want to talk!" Maria accuses Vanya of having greatly changed from the man of convictions and "shining personality" she once knew. Voynitsky replies bitterly that his shining personality has never illuminated anyone. In the past year, he has abandoned all scholarship and finds himself unable to sleep in his anger over having let life go by.

Unimpressed Sonya chides her uncle for being boring. Maria observes that Vanya himself is at fault for his failure: "Something useful ought to have gotten done," she remarks. Voynitsky retorts that not everyone can be a "writer perpetuum mobile" (or writer in perpetual motion) like the professor, ironically referring to both the professor's lackluster career and rheumatism. Sonya protests, and Voynitsky silences himself. A number of awkward pauses ensue. Yelena comments on the "lovely weather"; Voynitsky remarks that in such weather one could hang oneself. Telegin begins to play a polka on a guitar as Marina returns and calls the chickens. The group listens in silence.

A workman then arrives and summons Astrov to the factory. Annoyed, Astrov prepares to leave and invites Yelena and Sonya to his forest preserve. When Yelena wonders if forestry can be all that interesting, Sonya passionately recounts Astrov's efforts to stop the devastation of the forests and proclaims the benefits of conservation for civilization. Joining Sonya, Astrov decries man's impulse for destruction, extolling the beauty of nature and man's capacity to create; by saving trees, he leaves his legacy to future generations. Taking a drink of vodka, Astrov then admits that perhaps only an "eccentric" could think thus and departs.

Yelena and Voynitsky then walk to the veranda. Yelena reproaches Vanya for once again criticizing her husband. Vanya protests: "If only you could see your face, the way you move Even to go on living seems too much of an effort for you!" Yelena rejects Vanya's sympathy: just as man would destroy Astrov's forests, Vanya would destroy her.

Yelena then digresses, revealing that Sonya has fallen in love with Astrov and intimating her own interest in him. When she abruptly asks Voynitsky to stop looking at her, he desperately declares his love. Yelena immediately moves to silence him, and the two move toward the house, Voynitsky imploring, "Just let me talk about my love and this alone will make me the happiest person in the world." "This is torture" Yelena replies. The scene closes with Telegin's polka, and Maria making notes in the margin of her pamphlet.