The central theme of Art explores the core of friendship. The story revolves around the interactions of three middle-aged men who have been close friends for around fifteen years. This long-standing bond is challenged when Serge purchases an expensive piece of art. The intensity of this situation highlights the fragile nature of friendship, as a small change in the status quo brings unresolved tensions to light. In a Boston Globe review, Anne Marie Donahue observed that Art examines ‘‘the sadness and confusion that can result when long-term friendships collapse for no clear reason.’’ Likewise, Benedict Nightingale noted in a Times (London) review that Art delves into ‘‘the politics of friendship,’’ touching on themes of ‘‘dominance, control, insecurity, and the role of compromise and fibs in most relationships.’’ By the end of the play, Serge and Marc agree to ‘‘reconstruct’’ their friendship, planning a ‘‘trial period’’ of reconciliation. While their friendship seems temporarily restored, its fragility is apparent, leaving the future of their relationship uncertain.

Marc views Serge’s purchase of the Antrios painting as a symbol of a major change in their friendship. Marc notes that Serge once looked up to him as a role model, embracing many of Marc’s fundamental beliefs and perspectives. However, as time has passed, Serge has begun associating with a new group of individuals who don't necessarily share Marc’s outlook. Everett Evans commented in the Houston Chronicle that the painting in Art "symbolizes the friends drifting apart, Serge’s rejection of his former mentor Marc, and his shift to a different social circle with new values." Marc admits that these shifts in their friendship make him feel deserted by Serge.

Marc's identity is deeply connected to the notion that his friends respect him and look to him when forming their views. He feels threatened by Serge's demonstration of independent thinking and taste, seeing it as a personal slight. As a result, Marc's feelings toward his friends are more self-serving, aimed at enhancing his own ego rather than showing true affection. Marc confesses to Serge, "I loved the way you saw me," revealing that his affection is rooted in Serge's perception of him, not in Serge's unique qualities. Serge responds, "Everything has to revolve around you! Why can’t you learn to love people for themselves, Marc?" Marc's insecurity about his own identity leads him to feel unloved by his friends whenever they show any independence from him.

Although no women are featured in Art, the conversations between the three men reveal significant insights into their relationships with women. More importantly, the play's main theme is underscored by the tensions among the friends, which are reflected in their remarks about each other's romantic partners. Yvan is engaged to a woman named Catherine; Marc is either married or in a long-term relationship with a woman named Paula; and Serge is divorced from a woman named Francoise, with whom he has two children. As the tensions escalate among the friends, they begin to vent their frustrations by criticizing each other's relationships.

Serge seems the most hostile towards the women in his friends' lives, likely due to his own divorce and apparent bitterness, compounded by his lack of a stable relationship. When the dispute over the painting heats up, Serge calls Catherine a "gorgon" and warns Yvan that marrying her will result in "a hideous future." Yvan responds that Serge is "not necessarily the person I'd come to for matrimonial advice," reminding him, "You can't claim to have been a great success in that field." Later, Serge makes derogatory comments about Paula, provoking Marc to the...