What does Eddie learn from the captain?
Regarding this, what did the captain teach Eddie?
The Captain He explained that, although he shot Eddie, he kept his promise by not leaving him behind and even sacrificed his life so Eddie and two other soldiers were able to live. He also teaches Eddie that when one loses something, they often gain something else.
Similarly one may ask, what does Eddie learn from Ruby?
Ruby, after whom Ruby Pier was named, happens to be Eddie's third person - not only because of their shared connection to the amusement park but because Ruby happened to be in the hospital room where Eddie's father died. She teaches Eddie the lesson of forgiveness by revealing the truth behind Eddie's father's death.
Ruby offers Eddie a new perspective on the circumstances surrounding his father's death. Eddie used to think that his father caught pneumonia after making a drunken decision to jump into the freezing ocean. However, it turns out that Eddie's father was saving the life of his oldest friend, Mickey Shea.