Back in the days of knights, dragons, damsels, and stone towers, chivalry and courage went hand-in-hand. Chivalry was the code the knight lived his life by, and it included such virtues as honor, gallantry, courtesy, generosity, valor, and even love. The knight who lived by chivalric conduct was considered a true knight. Today, chivalry isn't too much in fashion—possibly because knighting isn't as chic as it used to be. But in Prince Caspian, chivalry makes a modern-day comeback with heroes like Peter and Caspian suggesting that the best of the chivalric code can be of use today. Sure, we might not call it chivalry—principles seems more up-to-date. Slice how you'd like, it's in the book all the same.
The principles of Prince Caspian come directly out of classical romance stories (by which we mean true romance and not lovey-dovey romance).
Although he's the protagonist, Prince Caspian's principles are molded more by the people around him than by any of his own decisions.