How is Pride and Prejudice by Austen a conservative text, and what does it say about the class system?"Julian North describes [Austen's work] as a...

There are two senses in which
critics categorize Austen and Pride and Prejudice as conservative:
(1) as socially conservative, which includes class divisions; (2) as politically
conservative, which includes women's rights. The definition
of conservative that is applicable combines two meanings: "preserving established
customs"; conventional, traditional, resisting change (Collins
Dictionary). When critics like Julian North (quotation above) call Austen and
Pride and Prejudice a "conservative" author and text, what is meant
is that she does not attempt to stir social reform to the existing social class system
or any other institution (e.g., marriage) or custom, unlike Charlotte Brontë
(Jane Eyre, 1847) or Charles Dickens (e.g., Little
Doritt, 1857).

One textual support for the idea
of conservatism is that Elizabeth's initial emotionalism is overruled by
reason (a favorite theme since her juvenilia) when she accepts Darcy and
enters a marriage that represents the social and class
ideal: poor upper class gentleman's daughter marries wealthy upper class
gentleman's son. Another textual support is that Charlotte, who is the story's voice of
reason, yields to practical social realities and marries Collins
for economic and social class advantage, not for
love.

I hope
you will be satisfied with what I have done. I am not romantic, you know. I never was. I
ask only a comfortable home; and considering Mr. Collins's character, connections, and
situation in life, I am convinced that my chance of happiness with him is as fair as
most people can boast

A third
support is that Lydia and Wickham are forced by Darcy and Uncle Gardiner, at great
monetary cost, to become respectably married; this preserves the
entire family from social class disgrace and ostracism
though at great personal cost (the family connection with Wickham is onerous and the
drain on income).

For a fuller understanding of the issue,
three opposing arguments against conservatism are implied
in Pride and Prejudice. The very act of writing and
publishing is a form of action for women's
reform. Women were not accepted as having high intelligence and
understanding, which makes Sir Walter Scott's assertion of Austen's genius even more
meaningful than otherwise. For a woman to take action and go against the conservative
reality--like Austen and Fanny Burney (Evilina, 1778) and Ann
Radcliff before them and Charlotte Brontë after them--was an implied protest against
conservatism and affirmation for reform.

Another argument
against conservatism is the implied protest against class
order evident in Elizabeth's rebellion against
marriage to her cousin and against her parents' express interest and wishes
(at least her mother's wishes, though one must suppose that, though saying otherwise,
Mr. Bennet would not be unhappy to know his early wasteful ways were redeemed and his
widow and daughters would be provided for because of a marriage to the recipient of the
entail, Mr. Collins).  

Another argument against
conservatism is the implied protest (1) against entails of wealth and
property away from women and (2) against restricting
women's power and authority: whatever haughty things Lady de
Bourgh might be, she is wealthy and powerful in her own right because the
males in her family line recognized women's value, competence and worth and protected
her wealth, status and authority through available legal means.