In the wintry Klondike wilderness, fire is as crucial to survival as is food or water. For the man, fire represents the desire and ability to continue living. The title emphasizes the importance of fire in the story. The man’s survival hinges on his physical capability of performing a task that is regularly taken for granted: building a fire.

During his lunch break, the man is easily able to build a fire, allowing him to eat and persist. Much like how he doesn’t fully respect the freezing temperatures, he also doesn’t appreciate the fire’s warmth. Through instinct, the dog does value the fire and doesn’t want to leave it. The dog inherently understands the Klondike’s danger, and that the fire’s warmth is crucial to survival.

Later, through detailed description, the story’s tension climaxes when the man fights for his life, the continuance of which is entirely dependent on his ability to build a fire. When he fails, he desperately clings to his life, but the cold soon kills him.

As he hikes, the man often thinks about the advice given by the old man of Sulphur Creek. The old man has advised him to never travel alone across the Klondike when the temperature is below negative 50 degrees.