Themes are the fundamental and often universal ideas explored in a literary work.

Loneliness and the Need for Companionship

While Winnie never uses the word, she is constantly lonely and depends heavily on the assurance that Willie is conscious and listening to her. She doesn't ask much of Willie, but needs to feel that her words an impact on someone else, and are not simply externalized thoughts. The song she loves so much is a duet about love, what Winnie longs for most, yet her love of and dependency on Willie is reciprocated only briefly at the end of the play. Perhaps the play's setting is merely an extension of their married life, one that became a stale, lifeless coupling over time. Winnie compensates for this loneliness through her imagination. She recites lines from poems and plays in an attempt to commune with their authors, and conjures up the image of Shower/Cooker and his fiancée. The imaginary couple watches and discusses Winnie, and gives her the feeling of being cared for, something she doesn't get with Willie. Her desire to be watched is realized in the theater, where the audience is a stand-in for the perplexed imaginary couple. Perhaps only through art can we defeat our loneliness.

The play also revolves around pairings. The sounds of Winnie's and Willie's names suggest a light ascent and heavy drop, respectively, and Winnie's sensation of being "sucked up" into the air, compared with Willie's crawling and life in his hole, supports these movements. It seems less likely that they complement each other, and more that they head in opposite directions, as when they laugh at the ant for different reasons, except for at the end, when they share a brief moment of togetherness. The two-act structure of the play and the doublings of the bell—it rings twice in the morning, and rings both to wake them up and signal the time for sleep—sustains the atmosphere of couplings. The end of the play is ambiguous and lets the audience decide whether Winnie and Willie are brought together for good as they inch toward death, or if their partnership is just a temporary respite before they split up again.

Stasis Masquerading as Change

Rituals, such as Winnie's brushing her teeth and cleaning her effects, dominate the play's constrained but frequent actions. She performs the routines to fill up the empty hours of the long days, but the completion of each ritual also depletes her, causing her sadness, such that the ritual becomes a repetitive motion which grinds Winnie into a static, exhausting routine—she notes that holding up her parasol is fatiguing, but if she were in motion it wouldn't be. Moreover, nothing is really changed at all after the rituals are performed, and the entire day takes on the appearance of one large ritual; Winnie remarks that her burnt parasol will return to new the next day, and she acknowledges that the climate around her is always the same and will stay that way. If there are changes, they are so minute as to be virtually static. As the play nears the end, its silences and pauses increase, lending the impression that Winnie's and Willie's lives are dragging on ever more slowly toward a death they will never reach.

Failure and Emptiness of Language

Winnie often remarks that certain words are "empty" to her, and thinks about the day when words must "fail." Language is empty to her because it signifies nothing in her current world, only things from a past life Winnie cannot access; just as a hog is foreign to her and thus an empty word, since no hogs exist for her, the word "breast" is, by the second act, empty, as her breasts are covered up and essentially no longer exist. Likewise, "torrid" and "temperate" have no meaning for her, as the climate is always the same around her. Language fails, on the other hand, because it creates the illusion that true dialogue is being exchanged when, in fact, Willie is hardly a reciprocal conversationalist. Language is dependent on its social usage to have meaning, and since Winnie talks to herself the whole play, with little reaction from Willie, her words fail. Beckett throws in clues to the solitude that language conceals, as when hair is defined as a singular entity, not a plural one ("it," not "them"). The confusion begins when Winnie discusses brushing her teeth and hair, brushing "them," in one sentence. Hair's plurality in the sentence is an illusion, just as Winnie's speech is really a monologue no matter how hard she tries to get Willie to speak.