Love
The main theme of this play is love, in all its forms. Much of this love is unrequited. Indeed, many of the characters are wildly attracted to, and occasionally in love with, other characters who do not reciprocate their feelings. This begins with the count, who is desperately trying to convince Susan to begin an affair with him, despite the fact she is engaged to marry the man she genuinely loves, and despite the fact she has rebuffed his advances multiple times. Marcelina is in love with Figaro, although he is many years her junior and has no interest in her whatsoever. Dr. Bartholo has always been interested in the countess, but his affection was not reciprocated. Basil is in love with Marcelina but she barely notices him. Finally, Hannibal falls in love with nearly every woman he meets, especially the countess.
Figaro and Susan are genuinely in love, navigating the twists and turns of courtly life in hopes of one day being able to have a normal marriage and relationship. The love they feel for one another is pure and sits apart from the other affairs, with are by and large motivated by passing attractions and game-playing, rather than by genuine affection.
Betrayal
Another theme of the play is betrayal. The central betrayal is that Count Almaviva has a wandering eye and is looking to have an affair with Susan, in spite of both his marriage and Susan's imminent marriage to Figaro. His entire lusty narrative is motivated by a desire to betray his wife in order to find sexual novelty.
In response to this betrayal, the other characters devise their own plots to teach him a lesson. Figaro is a master of the prank, always looking to find a lighthearted way to betray people who need a little reality check. However, throughout the play, his strategies do not work, and the countess and Susan become the most successful pranksters. By the end of the play, they are able to show the count the error of his ways by concocting a plot whereby each will pretend to be the other in order to trick the count into having an "affair" with his own wife.
The Transgression of Social Propriety
There is a huge emphasis on social propriety in the play, reflecting the time in which it was written. The characters are often overstepping the bounds of what is socially acceptable, yet all the while taking these rules and standards very seriously, so as to protect their own reputation. For instance, the count has no qualms about having an affair with his betrothed servant on the night of her wedding—so long as nobody finds out. Additionally, much of the action of the play concerns characters being in rooms in which they are not supposed to be. Men find themselves in women's bedrooms, women's clothing, and hiding in women's dressing rooms. These transgressions are part of what motor the play's comedy, in that the audience is meant to delight in the ways that the characters find themselves in such scandalous and outrageous situations, ones which fly in the face of social propriety.
Class
It is the possibility of crossing class boundaries that drives much of the scandal, and thus the comedy, of the play. The count is trying to sleep with a servant, while the servants plot with the countess to dupe the count. Within the social structure in the castle, people have very different levels of power, yet the characters also know how to navigate these dynamics in order to gain the upper hand in spite of their class position. Figaro and Susan, due to their ingenuity and intelligence, are able to gain power and autonomy from within their subservient positions, while the count, in spite of his high status, often finds himself humiliated.
Even so, the play also addresses class differences in more complex ways. For instance, when Figaro believes that Susan is having an affair with the count, he delivers an impassioned soliloquy criticizing the aristocracy. He suggests that there are unremarkable and horrible people who are treated with great respect simply because of their status, while exceptional people get denigrated because of their lower positions. Indeed, this soliloquy proved so controversial at the time of the play's premiere that the king, Louis XVI, banned it until Beaumarchais could revise it to his liking.
Mistaken Identity
Mistaken identity is a major theme and motif in the play, with characters often affecting disguises in order to maneuver their way through the court. At the end of the play, the countess and Susan dress up as one another in order to dupe the Count, but they end up also duping Figaro in the process. Additionally, the innocent Hannibal gets caught in the crossfire, assuming many different disguises in order to avoid getting sent away by the count. The theme of mistaken identity and disguises ties in to the transgression of social propriety mentioned earlier, and also represents the ways that status and identity are so arbitrarily tied to more superficial appearances. One of the major comedic moments at the end of the play comes from the fact that—despite the fact that he is seducing his own wife—the count thinks that he is experiencing the novelty of a new lover. Even though it is still his wife, for the count he finds the experience as pleasurable as he imagined he would with someone new. Thus Beaumarchais suggests that the way we picture things in some ways determines what they are.
Gender
Gender is also a major theme that is touched upon in the play. A great deal of Countess Almaviva's angst about her marriage comes not only from the fact that her husband is cheating on her, but the fact that he is entitled to do so as a man. At several points, she discusses the double standard placed upon her: that she must be completely faithful and vigilant as a wife, while he carries on irresponsible and messy affairs. This sense of injustice around gender is what motivates her to pull such an elaborate prank on him and expose his misdeeds.
This double standard also occurs when Figaro believes that Susan is having an affair with the count and starts to pursue an affair with the woman he believes to be the countess. In this arrangement, as in the marriage between the count and countess, a woman's value comes from her fidelity, while a man is held to a much lower ethical standard.
Sex
In the play, sex is often confused with love. The count, for example, is a particularly lusty man who is interested in pursuing affairs with other women even though he is married to the countess. The women look to expose his libidinous dalliances through a prank, revealing the ways that sexuality can become so transgressive.
Sexuality is also explored through the adolescent characters in the play, Agnes and Hannibal, who are both consumed with passionate feeling. Hannibal harbors an erotic devotion for the countess, his godmother, while Agnes is implied to be rather sexually free herself. As young people, they represent the ways that sexuality and love blooms in adolescents, often in comical and over-the-top ways.