David Garrick, the writer of this prologue, was one of the most famous actor and producer of his time. He wrote this prologue as a satire, where the character "Mr. Woodward" would be in mourning, because comedy is dying, and that Dr. Goldsmith might prove the doctor, and She Stoops to Conquer the medicine, that will cease its death.
Though not written by Goldsmith, the play's prologue is useful in the way it provides insight into Goldsmith's purpose in the play. Obviously, the most explicit purpose is to make the audience laugh. The prologue also mirrors the trend in theatre that writers like Goldsmith were desperately trying to change. At the time popular theatre comedy was separated into what was commonly termed "sentimental comedy" and "laughing comedy." The former was concerned with middle-class morality and with praising virtue. The latter, which dated back to the Greeks and Romans and through Shakespeare, was more willing to engage in “low” humour for the sake of mocking vice.
Woodward suggests that a certain class of actor were dying out as sentimental comedy became more popular. So Goldsmith's play has an extra purpose: it must rejuvenate the joy taken in “laughing comedy”, which could be willing to be more stupid, to dramatize base characters and characteristics, and to mock even the characters who profess to be moral.