The key theme of superficiality in Lady Windermere's Fan is illustrated by a cluster of subtopics that include keeping up appearances, keeping up with the social expectations of class, and the hypocrisy of moral double standards.

Granted, these are typical themes in the genre of comedy of manners, which portrays, in a satirical way, the overzealous preoccupation of Victorians to appear successful, well-mannered, and "proper" in the eyes of society.

It can all be summarized in Lord Darlington's words:

If you pretend to be good, the world takes you very seriously. If you pretend to be bad, it doesn’t. Such is the astounding stupidity of optimism.

Wilde, the master of this genre, presents these themes from the very start of the play.

Superficiality and keeping up appearances are essential themes in Lady Windermere's Fan because they cause nearly every action in the play.

For example, right from the very start, we find Lady Windermere engaged in putting her roses together. The way it is described, one would feel almost jealous of this lucky lady. She is a young, beautiful, and rich woman, who describes herself as someone who knows right from wrong and prefers people to be "proper" without any excuse. And yet, later on in the play, we will see her deviating from her moral compass and contemplating an elopement with another man.

The themes are also evident with Lord Windermere, the Lady's husband. He has one key action in the play: to protect his wife's social persona. He does this by keeping her from learning that her real mother, Mrs. Erlynne, is not only alive but also a mean, socially shunned woman who is planning to expose who she (Erlynne) really is. This would cause Lady Windermere a lot of shame. The appearance of domestic perfection that she embodies would come crashing down.

Lord Windermere also has to watch out for his own reputation. After all, according to the gossipy Duchess of Berwick, Society (with a capital S) "knows" about his dealings with the Erlynne woman. Moreover, Society "has been talking about it" behind the Windermeres' back, apparently having a field day with the situation.

On the other side of the spectrum, there are the characters who are shunned, or should be shunned, from society and yet try very hard to go back to it or continue to keep appearances.

The first is Mrs. Erlynne, Lady Windermere's real mother (unbeknownst to Lady Windermere). The woman was shunned from the "good" society for abandoning her husband and daughter to elope with a man. Still, she wants to be back in that circle. She resorts to blackmail and threats to Lord Windermere as ways to buy her silence. However, she still wants to disclose the truth to her daughter, even though she knows how insulting it would be for the sanctimonious Lady Windermere to find out who her mother is.

The second is Lord Darlington, who is known by everyone to be a dandy and "vile" as far as his morals go. He is still accepted in society only because his name, rank, and relations make him, by Victorian double standards, a member of the "polite" society. Hence, he keeps up the appearance of someone who is of a higher social bracket—but only in name and position. If he had no rank or position, he would probably receive the treatment that he really deserves, and nobody would go near him.

Therefore, the society in which Lady Windermere's Fan is set is very duplicitous. This is a time in which people presented themselves with fake and superficial appearances of righteousness and self-importance. As such, keeping up with appearances and with the social expectations of "class" were of utmost importance for survival.

While the play is just a representation of real life, Wilde knew all too well that things could get just as ridiculous and fake in everyday English society as he presented them in his plays. It is sometimes hard to tell with Wilde if, in his plays, art imitates life, or life imitates art.

There are two major theme's in Wilde's play.

The first is hypocrisy. Hypocrisy is insincerity; that is, saying or acting in a way that is not true or real. Most of the characters in Wilde’s play accept hypocrisy as a necessary component of their social world. For example, Dumby agrees with Mrs. Stutfield that the season has been ‘‘delightful,’’ and in the next breath agrees with the Duchess of Berwick that it has been ‘‘dreadfully dull.’’

The second major theme is that of the "bad mother." This play was written during the pinnacle of First Wave Feminism as women fought for suffrage. Women who wanted to "leave home" were often portrayed as evil, abandoning their families for realms that were "rightfully" male (politics, work, etc.). The "bad mother" is Erlynne in Wilde's play, who leaves to pursue her own life.

What social aspects are found in the play Lady Windermere's Fan?

As is true of most of his plays, Lady Windermere's Fan by Oscar Wilde is in many ways a drawing-room comedy, involving witty dialogue among members of the British aristocracy, replete with dandies and parties. Unlike Wilde's more successful plays, there is a more serious moral point hung on a somewhat clumsy plot structure.

The social critique has to do with first a double standard by which society in this period judged what was considered sexual misconduct, unfairly penalizing women and homosexuals while allowing, in particular, straight men to stray without being punished. It specifically directs its criticism at the hypocrisy of punishing women who commit adultery or strive for divorce, without punishing their male partners.

Mrs. Erlynne, who turns out to be the mother of Lady Windermere, actually proves the most moral of the characters in the play.

What is the theme of Lady Windermere's fan?

Enotes users are only allowed one question at a time, so I edited your question to the gist of it, and will answer the most important one which is about the theme of Lady Windermere's fan.

The play is about Lady Windermere, a young woman whose impeccable character makes her the proper example of the pruddishness that was rampant in the times of Oscar Wilde.

This woman receives the news that her husband has been visiting a woman, a Mrs. Erlynne, who has come to London to be taken back into society. Lady Windermere also finds out (through the Duchess of Berwick) that her husband has spent countless amounts of money on Mrs. Erlynne to help her "settle in."

As she confronts her husband, she still does not get a definite answer as to why he is taking care of this woman. She also does not understand why she is now obligated by her husband to not only accept her in her house as a guest for her birthday party, but that she also must extend an invitation to other visits. This would make those do not know Mrs. Erlynne acceptable in the fashionable set of the London upper classes.

Slowly we realize that the money that Lord Windermere has been giving this woman was under a form of blackmail, because the woman's main interest is to marry well, perhaps even with a Duke, or someone of title for marriage.

Once she marries into the ranks, she will be able to reveal the truth. She is the real mother of Lady Windermere. Her shame at her lack of rank, title, money, and class would have never allowed her near her daughter.

However, Mrs. Elynne chooses the wrong way to convey her need. She uses blackmail, lying, and deception, regardless of whether her actions will mend ties with her daughter or not.

Therefore, the theme of the novel is deception versus goodwill. When Lady Windermere believes her husband is cheating on her with Mrs. Erlynne (which was not true), she becomes Lord Darlington's lover as a way to get back at her husband.

Again, deception (self-deception in this case) is used for the sake of making up for lost love. Yet, the story shows that, in the end, deception will lead nowhere. The past and present of each individual is an individual's own making and creation. Mrs Erlynne  eventually has to leave again, but does so without confessing her secret. Lady Windermere is caught within the fire of jealousy and Mrs Erlynne's defending her from committing adultrywith Lord Darlington.

The fan is what unites them, since it could have been proof of deception from Lady Windermere and Lord Windermere.  Once Mrs. Erlynne takes the blame for the fan which is left "by accident" at Lord Darlington's house, her reputation goes back to being bad. She has to live with deception once more, a deception of which she is not guilty. Likewise, the Windermeres continue to pretend that deception never takes place, and pretend to go on with life as usual, deceiving themselves and absorbing the huge blow that their marriage takes.

Hence, deception versus good will shows that what begins in chaos, ends in chaos.