The importance of language as an important source of humor in Oscar Wilde's play The Importance of Being Earnest is based on Wilde's ubiquitous use of sarcasm, irony, epigrams, paradoxes, and mockery to identify the unique characteristics of the upper classes of Victorian London.
Oscar Wilde is represented in character of Algernon. Wilde uses Algernon as a mouthpiece to voice his own observations about the qualities of the aristocracy as individuals. Namely, that the aristocrats love to live above their means and appear to be wealthy, that they are classicist and bigoted, that they are hypocrites, holier than thou, and swear by prudishness while leading double lives.
This being said, the dialogues that are intended to aristocrats such as Lady Bracknell, Algernon, and Gwendolen are filled with contradictory statements that show the double standards of the rich. Lady Bracknell is Wilde's focal point as to who will speak the most nonsense, as she clearly tells Jack upon learning that he is an orphan:JACK:I have lost both my parents.
LADY BRACKNELL:Both?…To lose one parent, Mr. Worthing, may be regarded as a misfortune; to lose both looks like carelessness.
This is how Wilde uses the ignorance of the aristocrats as material for jokes and for basically laughing at them, while letting them laugh at themselves. That is the basics of Wildean dialogue in theater.