Why did Shakespeare use prose?

Answer 1

Verse, although it closely mimics the natural rhythms of English speech, is still unnatural. Its rhythms give a sense of gravity, power and intensity. The words take on more potency from the regular rhythm. But sometimes this is not what Shakespeare wanted to convey. Where the person speaking was saying something silly, or was poorly educated, or was losing his grip on reality, then the irregular and much more natural rhythms of prose convey this much more effectively. Remember that "natural" in Shakespeare's day was not a compliment--to call someone a "natural" was to call him an idiot. The Renaissance attitude was that artifice improved on nature, and make things, and people and speech better than nature. Nevertheless, some extraordinarily potent dialogue in Shakespeare was written in prose, such as the masterful Act IV Scene 6 of King Lear, which moves from prose to jagged irregular verse to regular blank verse and back depending on how sane the King is at any one moment.

Answer 2

Shakespeare used prose in his plays to create a contrast in style and rhythm. Prose was typically used for common characters or moments of everyday life, while verse was reserved for nobility and heightened emotions. This allowed for a dynamic range of expression and a way to differentiate between characters and their social status.