Blind and Prejudiced

If Mr. Darcy, from Pride and Prejudice, split Mr. Bingley and Jane Bennet up because of the distaste he had in her family, why then did he ask for the hand of Miss Elizabeth Bennet when she was in fact from the same family?

If you passed a dead cat in the middle of the road and saw it there still a week later, would you pull over and scrape it off the road?