What types of things does pride interfere with?

As Mary says in Chapter 5, "human nature is particularly prone to [pride]." Throughout Pride and Prejudice, pride prevents the characters from seeing the truth of a situation. Most notably, it is one of the two primary barriers in the way of a union between Elizabeth and Darcy. Darcy's pride in his social position leads him to scorn anyone outside of his own social circle. Meanwhile, Elizabeth's pride in her powers of discernment cloud her judgment. These two find happiness by helping each other overcome his/her pride. Outside of Elizabeth and Darcy, however, Austen seems pessimistic about the human ability to conquer this character flaw. A slew of secondary characters, like Mrs. Bennet, Lady Catherine, Mr. Collins, and Caroline Bingley, remain deluded by personal pride throughout the novel.