Gossip
Gossip is perhaps the most central theme of The School for Scandal. Gossip, or rumors, may be true or may be false; in general, however, gossip is spread by both unofficial channels (word-of-mouth) and official channels (newspapers). Since word-of-mouth spreads faster, gossip is mostly spread in the play through that channel, but it is clear from discussions between characters that the spreading of rumors through newspapers has a particular way of spreading information far and making it seem credible. The main rumor spread in the play is that Charles and Lady Teazle are having an affair (spread purposefully by Lady Sneerwell, Joseph, and Snake), but other rumors arise and circulate as well, such as Charles's debt, Joseph and Lady Teazle's affair, and Sir Peter being wounded in a duel.
Marriage
Marriage is another key theme of the play. This theme is mostly explored through the troubled marriage of Sir Peter and Lady Teazle. Sir Peter and Lady Teazle are different ages, come from different backgrounds, and seem to have different opinions about how people in the upper class should act; Lady Teazle believes she needs to keep herself integrated by spending money to stay in fashion and taking part in gossiping and judging. Sir Peter, on the other hand, would rather they live more simply and morally, and seems to not have expected this behavior from his wife. This says something about the way their relationship progressed and the way that husbands and wives generally behaved with one another in Sheridan's time. Though the couple attempts to be friendly at times, the pressure Lady Teazle feels from society, especially as an outsider, damages their marriage. Interestingly, Sheridan also does not seem to believe that an affair necessarily means the end of a relationship: while the constant arguing in the first half of the play does force the couple to contemplate separation and perhaps drives Lady Teazle to pursue the affair, Sir Peter finding out about this actually gives him hope and confidence that his relationship with his wife may strengthen from her remorse.
Gender
Gender is an important theme in The School for Scandal, especially as it interacts with other themes of the play such as gossip, marriage, and family. Women in upper-class, 18th-century England were generally viewed as less than men, and were treated as objects. In this play, they play two main roles: daughters and love interests. Lady Teazle even comments directly on these two options open for women, and the different power structures in the two: she tells Sir Peter, "if you wanted authority over me, you should have adopted me, and not married me"(p.47). In fact, Sir Peter is shown to have little authority over either his wife or his adopted daughter (or ward) Maria, who continues to lust after Charles and refuse the love of Joseph, despite her substitute father's wishes. Gender is also important to the theme of gossip because much of the gossip, especially the more trivial gossip, is focused on women. For example, in one long conversation, a group a gossipers discuss the makeup use of a few women who are not shown directly in the play. In another case, the men at Charles's house sing a song about different kinds of women, remarking on particular aspects of their physical appearances and characters.
Family
Morality in The School for Scandal seems to be most judged by the way you treat your family. This theme is shown through the comparison between Charles and Joseph Surface, brothers who both seek inheritance from their rich uncle Sir Oliver Surface. Sir Oliver goes to each in disguise. He goes to Charles disguised as Mr. Premium, a money lender, and is appalled when Charles agrees to sell the collection of their family's portraits. This act represents him disregarding and disrespecting his family and lineage. However, he refuses to sell the portrait of Sir Oliver, and Sir Oliver completely forgives him. Sir Oliver goes to Joseph, who is generally regarded as the more moral and proper brother, dressed as Mr. Stanley, a destitute family member. Joseph is shown to lie and not help Mr. Stanley, even though Sir Oliver knows he has the money to do so. However, Charles, who is deeply in debt and thought to be a selfish young man, does send 100 pounds to Mr. Stanley. Weighing all of this, Sir Oliver decides that Charles will be his heir. This shows that, other moral failings aside, Sir Oliver sees the loyalty and willingness to support one's family as the most worthy trait in a man. It can be surmised that Sheridan wanted to promote this value, especially in cases where it might conflict with perceived social propriety.
Politics
Satires, like The School for Scandal, are inherently political. While farces simply parody aspects of society through exaggeration, humor, and irony, satires do all this while pushing a particular message about an aspect of society that the author thinks needs to change or receive more attention and understanding. In this play, the theme of politics intertwines with the more general theme of gossip or scandal. It seems that there were not laws in place at the time to protect individuals from false rumors, or slander, which Sheridan shows has the power to ruin people's reputations and cause unrest in society as a whole. Sheridan challenges this through the character of Sir Peter, especially in dialogue with Lady Sneerwell. Lady Teazle challenges him, "Would you restrain the freedom of speech?"(p.53), and a scene later he has a prepared retort when the subject arises again, responding "if [parliament] were to consider the sporting with reputation of as much importance as poaching on manors, and pass an act for the preservation of fame, I believe many would thank them for the bill...in all cases of slander currency, whenever the drawer of the lie was not to be found, the injured parties should have a right to come on any of the indorsers"(p.67-8). Sir Peter believes punishment should be wrought both on the original creators of the rumor and those who spread them, making illegal much of what causes the conflicts of the play.
Physical Appearance
Physical appearance was clearly of great importance in the upper class in 18th-century England. This is of particular importance in this play since it is a comedy of manners, meaning that it focuses on upper-class social customs, and since drama itself as a medium focuses on physical appearance more than genres that are purely textual. Physical appearance in The School for Scandal intersects with the theme of gender in that the physical appearances of women are more remarked upon due to their lower status in society. For example, there is a long, gossip-filled conversation between men and women alike about the makeup habits of some women who are not seen onstage in the play (one woman in particular is criticized for using makeup on her face but not blending it with her neck, creating an effect like an old statue whose head has been mended back onto its body (p.59)). In another scene, a group of men at Charles's house sing a song about different kinds of women, focusing particularly on their different physical characteristics such as having light or dark skin and having or lacking dimples (p.110).
Money
Since The School for Scandal, as a comedy of manners, focuses on the lives and flaws of upper-class people, it is fitting that money or wealth is a strong theme in the play. A major question in the play is whether characters and the audience should believe Charles or Joseph to be the more moral and/or worthy brother. Joseph is shown to be wise and proper but stingy with his money, while Charles is fun-loving and spends himself into debt but is willing to give money to a poor relative, valuing family over his own wealth. Money is also the main issue that plagues Sir Peter and Lady Teazle's marriage, since she likes to (and feels the need to) spend more lavishly than he approves of. She seems to do this to try to stay in fashion, and thus in good standing, with high society. Sheridan thus shows how money played an important role in social standing, often to the point of causing interpersonal difficulties.
