quickly gives rise to a discussion of the merits of humility and pretense.  Bingley, once again demonstrating his eagerness to please and be pleased, comments that his penmanship is astoundinly horrible, to which Darcy comments that Bingley really must be proud of his defects and is only projecting false humility.  Mr. Bingley bears his friend's censure very well.  In this chapter, Darcy continues to be serious and circumspect, whereas Austen portrays Bingley as being very jovial and good-natured.  In the end, Darcy points out that Mr. Bingley dislikes arguments, and the discussion ends.

In both of these pairs, there is a secondary individual and a primary one. Bingley and Jane are secondary while Darcy and Elizabeth are primary. The interesting paradox (seeming contradiction between truth and what is) is that the two secondary individuals teach the two primary ones lessons and are proven correct in situations where the primaries are proven incorrect. The foundation of each of these pairs is a deep mutual bond of love, esteem, admiration and friendship.

While Bingley and Jane are, for the most part, followers of Darcy and Elizabeth, respectively, they are also the voices of reason while Darcy and Elizabeth are the voices of emotional reaction. This may seem an odd statement to make about Darcy, but his censure of Elizabeth at the Meryton ball was based entirely on feelings: he didn't feel comfortable with strangers; he didn't feel there was status in dancing with someone whose beauty was of secondary lustre; he didn't feel inclined to talk to anyone not in his own party (Bingley, Mrs. Hurst, Miss Bingley, Mr. Hurst). In contrast, Bingley and Jane represent reason throughout when they urge their friends to be more tolerant and open (Bingley-Darcy) or to be more accepting and generous (Jane-Elizabeth).

Between him and Darcy there was a very steady friendship, in spite of great opposition of character. Bingley was endeared to Darcy by the easiness, openness, and ductility of his temper, though no disposition could offer a greater contrast to his own,

In the end, Bingley's willingness to disregard Jane's family and connections and accept Jane for herself proves correct while Darcy's impulse to withdraw from the Bennet family and connections proves incorrect. In the end, Jane's willingness to have generous and accepting opinions of acquaintances proves correct (except as regards Wickham and the Bingley ladies who were represented as being bad beyond her previous experience), while Elizabeth's impulse for instant prideful and prejudicial likes or dislikes proves incorrect.

[Elizabeth] "Pleased with the preference of one, and offended by the neglect of the other, on the very beginning of our acquaintance, I have courted prepossession and ignorance, and driven reason away, where either were concerned. Till this moment I never knew myself."

The relationship between Mr. Bingley and Jane Bennet in Jane Austen's novel Pride and Prejudice is meant to represent an inverse reflection (known as a foil) of the dynamics that take place between Darcy and Elizabeth. A foil, in literature, is defined as any sub-character (or secondary character) that is used to contrast the main character (or an idea meant to contrast the main idea).

You asked how a (secondary) pair of characters help highlight the main characters of the story. The answer is that Austen, and many other authors, utilize the foil technique as a way to allow the reader to contrast the two situations and, in an sort of interactive way, come up with solutions, conclusions, and comparisons that may help solve the central problem of the story.

In all, these techniques are also effective in establishing a strong bond between the reader and the author. It always works well. Therefore, to concisely answer your question, the way in which one character highlights another is by foiling it.

To illustrate this explanation, think of how Jane and Bingley seem to be quite alike: Both are a bit shy, sympathetic to everybody, and none of them have the gall to take the first step in declaring love for each other. In fact, their relationship is so passive that even Charlotte Lucas wonders when "anything official" would take place. Similarly, Mr. Bennet judges them to be so complaisant with everything that he feared that they will end up failing in the financial sector. What Mr. Bennet basically declares is that, to him, Jane and Bingley are so alike (and sort of airheaded) that he worries about them.

In a huge contrast, we find Austen clearly focusing on the relationship between Darcy and Lizzie. They are both passionate and sort of enigmatic. He is proud, aristocratic, and  prude. She is prejudiced, independent, and an outspoken smart-mouthed girl. Both hate each other, both love each other, both get confused with each other....it is a roller coaster with Darcy and Elizabeth. And, yet, everything gets fixed happily in the end.

However, it would have not been as effective to show the one sided aspect of Darcy and Elizabeth without first presenting us with the story of Jane and Bingley. Just as we have had enough glurge with those two, the action begins: We see the darker side of the love moon in Lizzy and Darcy.

Conclusively, the use of a foul to highlight the unique characteristics of the main character of a story is an effective method to bring the reader closer to the main character. It allows the reader to compare, contrast, and create connections to the story. That is always a positive thing in literature.

To some extent, Jane and Bingley's relationship shows Lizzie and Darcy the path of true love. There's little doubt that, right from the outset, these two lovebirds have fallen head over heels for each other. But with Lizzie and Darcy it's a completely different story. They're held back from expressing their true feelings by the twin vices of Darcy's pride and Lizzie's prejudice. To make matters even more complicated, there's quite a large gulf in social class between them.

Darcy's social snobbery and standoffishness initially prevent him from enjoying a meaningful relationship with Lizzie. By the same token, Lizzie's put off Darcy by his cold, aloof demeanor. Yet Jane and Bingley's love match shows them that it's possible to overcome the various barriers placed between them by their respective personalities and society's restrictive conventions.

Jane Austen uses the relationships between Elizabeth/Darcy and Jane/Bingley to show the reader two different types of emotional love.

Jane and Bingley's romance, on both sides, was love at first sight. Bingley believed Jane to be the "most beautiful creature [he] ever beheld" and Jane found him to be handsome, gentlemanly, friendly, and easy going. After meeting him, Jane raved to Elizabeth about how he is "just what a young man ought to be." Both were equally attracted to each other, but sadly, the reason why the match broke up was that Jane was too reserved to really express her emotion. She never showed Bingley how much she cared, so Bingley was easily persuaded that she did not care.

Austen uses Elizabeth and Darcy's relationship to show the other kind of emotional love. Not all emotional love is felt the instant you meet. Sometimes the strongest love can enter as meekly as a lamb. Also, there is often a very fine line between love and hate. Elizabeth first felt upon meeting Darcy that he was detestable. However, it did not take long for him to convince her that the opposite is true.

The two romances show two opposing sides of emotional romantic love, the kind that begins with a bang and the kind that begins very quietly.