This is a question that is entirely subjective and based upon the reader's interpretation of Brian. One thing that is made entirely certain about Brian's past before the fateful crash is that prior to being stranded, he had no training, formal or otherwise, in wilderness survival. In fact, it is often illustrated that he led the life of a perfectly normal kid. He enjoyed riding bikes and eating food, and while he did enjoy occasionally watching nature programs, there is no evidence whatsoever to suggest that Brian was in any way prepared to face the hardships that were presented to him in the blink of an eye.

Much of Brian's positive and can-do attitude comes from the tutelage of his English teacher, Mr. Perpich, who teaches Brian that he himself is his most valuable asset. It is the memory of Mr. Perpich's words that resonate within Brian and keep him from falling into despair. His memory of his teacher is in fact the first motivating factor that inspires him to begin looking for food and to ultimately survive.

Furthermore, Brian realizes that, at his core, he is a resourceful and strong person. Having no training, everything Brian learns, from what foods to eat to how to make a shelter, is learned through trial and error. We find through internal dialogue that Brian possessed a fairly negative opinion of himself before the crash, thinking of himself as weak. This ordeal, while terrifying, was the trial that Brian needed to prove to himself that he was a strong, independent, and willful person.