Gary Paulsen focuses on the theme of man versus nature in most of his work. In fact, he employs this theme to such an extent that his literary reputation has been built around it. Paulsen writes not only of man's struggle against nature, but also of his capability to live harmoniously with nature, demonstrating his love and respect for nature.
Brian's communion with the animals with whom he shares his surroundings demonstrates Paulsen's view that Brian comprises another element of the natural environment rather than a separate entity. He undergoes many of the same struggles that the animals experience. Brian's constant search for food, as well as his efforts to stay safe from the elements and from other animals, facilitates his understanding of them. His encounters with the wolf and the bear provide a particularly strong sense of affinity. While Brian initially fears these animals, he soon realizes that they do not intend to harm him. He establishes a sort of trust with the animals in the woods, and soon develops the ability to listen to his instincts in determining whether or not he faces danger. For example, during a second encounter with a bear, he senses he is unwelcome. Scanning the woods, he soon realizes that the female bear wishes to protect her nearby cub.
Brian grows not only to recognize nature's dangers, but also to marvel at its beauty. As he watches the tornado rip across the woods and the lake, he finds it at once "beautiful and terrible." Brian has tremendous struggles with nature, but it seems that this novel revolves to a greater extent around Brian's struggle with his own identity, using nature as the setting. The Canadian woods provide a sufficient distance from societal forces, his parents, and his friends; in this way his experience tests his sense of self. The natural setting, which is ideal for character development, tests Brian's strength, resolve, and patience.
Brian undergoes many transformations throughout the course of the book; perhaps most significantly, Brian learns the power of positive thinking. Initially, Brian's setbacks leave him frustrated, hopeless, and full of self-pity. He longs for home, focusing on the past rather than the future. Early in his stay in the woods, Brian recalls the words of his old English teacher Mr. Perpich. He constantly encouraged his students to think positively and to motivate themselves, saying, "You are all you have." This advice helps Brian to a certain extent, but he does not fully realize the import of positive thinking until a certain incident forces him to see it.
In Chapter 8, a porcupine awakes Brian and drives hundred of quills into his leg. He cries for a long time in pain and despair, but soon emerges with a new perspective. Paulsen writes that "later he looked back on this time of crying in the corner of the dark cave and thought of it as when he learned the most important rule of survival, which was that feeling sorry for yourself didn't work. It wasn't just that it was wrong to do, or that it was considered incorrect. It was more than that—it didn't work."
This realization provides Brian's first step toward mental resolve. Although he has several lapses in resolve, most notably when he attempts suicide, he generally grows toward a more confident and determined state of mind. The moose attack and the tornado injure Brian and destroy his shelter, but in the aftermath of these events, he demonstrates a remarkably positive approach to the situation, immediately taking action to rebuild and heal.