Provincial Life
One of the main issues that the Prozorov sisters have with their life is the fact that life in the country is not stimulating enough and provincial living is stifling their education and refinement. Irina and Andrei both worry that their educations are going to waste. At one point Irina says, in a panic, that she has forgotten the Italian word for "window," which suggests to her that living in the country has dulled her intellect. Andrei once dreamed of becoming a great scholar, but now the biggest ambition he can maintain is to become a member of the District Council. Masha is also disappointed in country living, particularly the boring life of a schoolteacher's wife, and longs for some adventure, which her affair with Vershinin provides. Additionally, the Prozorov sisters' distaste for Natasha rests in the fact that she is not refined or urbane and has unsophisticated taste. The major arc of the play follows the household as its members struggle to feel contented and at ease with their country lifestyle.
Love
The characters each experience love and longing in different ways. The eldest sister, Olga, is disappointed because she never got married or experienced love. Masha is disappointed with her marriage to the schoolteacher, but experiences a passionate romance when she meets Vershinin. Irina longs for love, but, as she tells Tusenbach in their final conversation, "My heart is like a fine piano no one can play because the key is lost." Meanwhile, Andrei feels deep love for Natasha, but eventually loses respect for her, and feels disrespected for her. Tusenbach loves Irina, but is disappointed when his devotion is met with indifference. Each of the characters struggles with their own disappointments when it comes to love and romance, and the play seeks to show the tragic complications of romantic love.
Class
A large part of the conflict between the Prozorovs and Natasha is the fact that they come from a higher or more sophisticated class than her. They criticize the way she dresses because they perceive it to be tacky and ill-matched in some way. Their opinions are a coded way of judging her for her class background and her provincial upbringing.
Irina is also someone who grapples with the issue of class, and particularly with her own privilege. She feels directionless and does not know what to do with her life, so decides to work to support herself. In this way, she is confronting her own relationship to class and trying to find a way to be more connected to the world around her. Tusenbach, a baron who came from a privileged upbringing, shares her desire.
Thus, class is a major theme in the play, even if it is not spoken of explicitly very often. The Prozorovs are a family who, since the death of the patriarch, has had to get used to living with more limited means, an upper-class family who must figure out their relationship to money, and come to terms with the fact that they might never be able to live the lavish and privileged life of their charmed Moscow childhoods.
Purpose
Irina struggles most with the question of purpose, wanting desperately to find something with her life. As the youngest sister, she feels like a world of possibility is outstretching in front of her, but she does not know how to fill her life with meaningful events and experiences. She decides that the most purposeful and meaningful thing someone can do with their lives is work, and Tusenbach, the man who loves her, agrees with this sentiment. They make plans to move somewhere together and start a life as workers, and even after Tusenbach is killed, Irina plans to carry through with this plan on her own.
Disappointment
Everyone in the play seems to get disappointed about something or another. Irina is disappointed by her work at the telegraph office, by the fact that they won't get to Moscow, by the baron Tusenbach as her husband. Olga is disappointed not to be married and by her position as the headmistress at the school. Masha is disappointed in her marriage and by the fact that she cannot be with Vershinin, the man she loves. Tusenbach is disappointed by Irina's coldness towards him. Andrei is disappointed by the fact that he will never become a scholar at a university, and Chebutykin is generally disappointed, feeling that life has passed him by. On the whole, the characters are a pretty sorry lot, plagued by disappointment and melancholy.
Philosophy
Vershinin loves nothing more than to philosophize, and he is self-aware about his desire to try and diagnose the ills of society and imagine a brighter future. All the characters are resigned and disappointed by life in various ways, but it seems that Vershinin has found that the best way through these conflicted feelings is to think in the abstract. He likes to imagine a time two or three hundred years in the future, in which everyone is happier and life is sweet and good. By imagining an ideal future, he is able to feel like his life has purpose, that the ways he is suffering now are in service of the people of the future. Tusenbach likes to philosophize as well, and Masha is charmed by Vershinin's attraction to a life of the mind.
Marriage
Separate from love, the institution of marriage is a major theme in the play, and often the source of a great deal of angst for the characters. Whether they want it or have it and don't want it, none of the characters in Three Sisters are especially happy in their marriages or with being unmarried. Chebutykin and Olga both wish they had gotten married and long for the promise of sharing their lives with another. Meanwhile, Masha and Vershinin are exceedingly discontent in their marriage; Masha is bored with Kulygin and Vershinin is in an unstable union. Andrei loves Natasha, but their marriage soon turns their relationship sour. The play grapples with the question of marriage, and seems to suggest that it never works out well.
