The main conflict in this story of survival is between human beings and nature. Another central conflict, however, is that between youth and confidence as opposed to wisdom and experience. The main character is a young man who believes that he knows the frozen wilderness, but he is still a tenderfoot who has not yet learned to respect the power of nature. Jack London shows early in the story that the tenderfoot lacks imagination, an asset he sorely needs when tested to the extreme by the harsh wilderness.

The man’s egotism is in conflict with his common sense. He does not understand humankind’s frailty and is too proud to admit his own. He does not comprehend the danger posed by an alien, hostile environment in which he can only survive by the full exercise of his native wit, instincts, skill, and cunning. Before the coming of winter, the old-timer from Sulpher Creek had warned him that one should always travel in winter with a partner and that one should never attempt to travel alone in temperatures colder than fifty degrees below zero. In his ignorance, the tenderfoot had laughed at the old-timer’s advice. Caught in the bitter cold, he is made to realize the value of the old man’s warning.

The tenderfoot scorns other precautions. Once caught in the wilderness, for example, he realizes the value of having a partner. He realizes, moreover, that a facial strap would have protected him against frostbite. Still, he manages to build a fire after he has broken through the ice, and, his confidence momentarily revived, he laughs again at the old-timer. Ironically, the man is doomed by his egotism and his stupidity. When the fire goes out, he has second thoughts about his superiority.

The plot development is incremental as the tenderfoot’s dilemma gets more desperate and as he unwillingly learns his lesson. His absurd belief in himself and his ability to cope with the situation is retained until the very end. Although he refuses to give up hope, it becomes increasingly clear that he has lost touch with reality. “When he got back to the States,” he fantasizes, as he is freezing to death, “he could tell the folks what real cold was.” Ultimately the man will die and be survived by his dog. The animal, a creature of instinct untainted by pride, is better adapted to the environment than the man.

"To Build a Fire" tells the story of an unnamed man who sets out on a nine-hour journey across the Klondike's unforgiving winter terrain to join his companions at a mining camp. Ignoring the advice of an old-timer, the man undertakes the journey alone, accompanied only by a dog. Due to a series of unfortunate events, he succumbs to the cold and freezes to death before reaching the camp. His actions and eventual demise underscore the story's themes of wilderness survival, the individual versus nature, and mortality.

Survival in the Wilderness

From the outset, it is evident that the man's chances of surviving the Klondike wilderness are slim. As a chechaquo, or newcomer, he has no prior experience with the region's brutal winters. Additionally, he is "traveling light"—on foot rather than by sled, carrying only a bacon sandwich, tobacco, matches, and some birch-bark kindling. He faces temperatures well below minus fifty degrees Fahrenheit. Despite warnings to avoid traveling "after fifty below" without a partner, his only companion is a half-wild husky—a "toil-slave" with no affection for him. At the best of times, the Klondike wilderness would seem alien to a newcomer because of its vast expanses of snow ("as far as his eye could see it was unbroken white" except for the trail). Traveling with minimal supplies and without a partner in such extreme cold makes the situation dire. Despite being "quick and alert" to his surroundings, the man's "bad luck" (falling into an icy river) and "mistake" (the second fire being extinguished by falling snow) turn into catastrophic events, ultimately sealing his fate.

The Individual versus Nature

The theme of the individual versus nature in "To Build a Fire" is closely tied to the struggle for survival in the wilderness. The story highlights the man's "trouble" as being "without imagination," which prevents him from contemplating "man's place in the universe," his "frailty in general," or the reality that humans can "only live within certain narrow limits of temperature." Throughout his journey, the man repeatedly faces his vulnerability against the immense power of nature, particularly the extreme cold. Each time he takes off his gloves, he is surprised by how quickly his fingers become numb. He is also astonished at how rapidly his nose and cheeks freeze and is amazed when his spittle solidifies in midair before it touches the snow. When he stops for lunch, his feet become numb almost immediately, which finally starts to frighten him. Even the dog, half-wild and more attuned to nature, feels "depressed" by the cold. With its natural instincts and thick winter coat, the dog endures the severe temperature long enough to head towards camp, where it knows it will find food and warmth. Devoid of fur or instinct, the man struggles.

Death

When his fire is extinguished by snow and his body faces the threat of hypothermia, the man must confront the reality of death. His initial reaction is to calmly recognize that the advice given by the old-timer was correct: "If he had only had a trail-mate he would have been in no danger now." This thought resurfaces as he fails to rebuild the fire. He then transitions to "controlled despair," followed by apathy, and eventually panic, making a last, desperate attempt to save his life by running on his frozen feet in hopes of reaching camp. The man's final response to death is an attempt to "meet [it] with dignity." His last words—"You were right, old hoss; you were right"—are part of an imagined conversation with the old-timer who had warned him not to travel alone. They also serve as an acknowledgment of nature's dominance over the individual.