"That is very true," replied Elizabeth, "and I could easily forgive his pride, if he had not mortified mine." (pg. 21)
Pride is the most important idea in Jane Austen's novel and this sentence perfectly illustrates this. The problem is not that Elizabeth OR Darcy is too prideful, it's that both of them are too prideful. Darcy has too much pride to see Elizabeth as an equal or even good enough to marry him and Elizabeth is too prideful to see past Darcy's cold manner and misguided actions. Austen's characterization of her two protagonists as too prideful shows that pride can lead to prejudice and severely color decisions.