The first instance of wit in The Importance of Being Earnest comes in the title. Puns are sometimes considered to be an inferior form of wit, but the pun on the name Ernest and the quality of being earnest is employed by Wilde in a variety of ways that elevate this form. Even if one discounts the disputed claim (made by Laurence Senelick, among many others) that earnest was a late Victorian slang term meaning "homosexual," the disparity between the quality of earnestness and the frivolity of Cecily and Gwendolen's concern with the name is a running joke throughout the play.

It is easy to give examples of wit in The Importance of Being Earnest, since almost every line provides one. Take, for instance, the opening lines of the play:

ALGERNON: Did you hear what I was playing, Lane?

LANE: I didn't think it polite to listen, sir.

The idea that it is bad manners to eavesdrop on other people's conversations is stretched here to the extreme notion that it would be impolite to listen to someone playing the piano. When Wilde does not take conventional ideas to extremes, he often inverts them, as when Algernon asks,

If the lower orders don't set us a good example, what on earth is the use of them?

This turns on its head the conventional idea that the aristocracy should set a good example for the lower orders to follow while containing the truth that, certainly within the play, the aristocrats do not in fact set such an example.