Which detail from "to build a fire" develop a theme about instinct versus intellect

A. One of the main themes of the story "To build a fire" by Jack London is the confrontation between man and the harsh northern nature. The main idea based on the fact that the confrontation with nature, to which it was necessary to adapt destroys the person. An important way to uncover this idea is the image of a dog, which, being a part of nature, does not resist it, and the person perceives as one of the natural forces.  

Confrontation of instinct and intellect throughout the story is underlined by small details, as for example, a person ignores the dog's attempts to keep it in the fire and not continue to travel.