I think that in the short story To Build A Fire by Jack London the theme is humans being far too prideful in their lives.
Examples of this would be:
- On the first page bottom paragraph ¨ It did not lead him to meditate upon his fertility as a creature of temperature , and upon man’s frailty in general, able only to live within certain narrow limits of heat and cold; and from there on it did not lead him to the conjectural field of immortality and man’s place in the universe¨. In this sentence it is as if the man figures he is almost invincible, as if he will never be killed by the temperatures and so there is no reason to think of it.
- “At half-past twelve, to the minute, he arrived at the forks of the creek. He was pleased at the speed he had made.” The man was proud of making such good time even though he almost lost his dog. He was vainglorious in how he chose to celebrate his victory without even considering the dog.
- “He realized that he could not kill the dog. There was no way to do it.” The man was about to kill the dog in order to save himself, but stopped because he had no actual way of killing it. He had no thoughts of remorse or conscience about killing the dog. He only thought about saving himself, and was selfish to do so.