Her father, captivated by youth and beauty, and that appearance of good humour, which youth and beauty generally give, had married a woman whose weak understanding and illiberal mind, had very early in their marriage put an end to all real affection for her.

– Jane Austen

Pride and Prejudice, Chapter 42. Mr. Bennet married his wife because of her beautiful appearance. He did not see the extent of her foolishness before he wed her. It is clear that Mr. Bennet no longer has no real love for Mrs. Bennet. Their marriage serves as a health warning to those who rush into marriage for beauty and appearances alone.