What is the main theme of Emma?

Social
class is a very important theme in the book, as it is in all of 's works. Regency England was a
very hierarchical society with clear boundaries between the respective classes. And it's clear
from reading that Jane Austen firmly believed in maintaining those
boundaries. At the same time, she insists upon the importance of the upper-classes'
responsibilities towards those poorer and less socially prominent than themselves.

We see this in Emma's well-meaning, but ultimately misguided attempt to instruct
Harriet Smith in the ways of Highbury society. It becomes painfully obvious that Harriet doesn't
really belong among the upper echelons of society; she is hopelessly out of her depth,
artificially elevated to a higher station by Emma's assistance. Thanks to Emma's ill-judged
intervention, Harriet gets ideas above her station, developing unrealistic expectations about
her future marriage prospects. Emma should have learned from the example of Mr. Weston. His
first marriage was to a woman of a higher social class, and her inability to adjust to a lower
standard of living was a major factor in their unhappiness together.