The narrative point of view adopted by London in “To Build a Fire” serves to give the story a clinically detached tone, which is not what we would ordinarily expect in a tale that deals with the slow death of a man in the midst of an icy wilderness. Yet this point of view fits in perfectly with London's naturalistic style of writing, which presents human beings as nothing more than objects in the natural world, like rocks, trees, plants, and sled dogs.
In London's crudely Darwinian world-view, man is nothing special; he's a part of nature, and as such, he must respect it. Unfortunately for the man in “To Build a Fire,” he didn't get the memo; he's so arrogant and foolhardy that he not only thinks himself separate from nature, but better than it, too. Thus, me makes his almost suicidal decision to embark upon such a dangerous expedition into the snowy wilderness of the Yukon.
While reading “To Build a Fire,” one could be forgiven for thinking that one were reading a scientific study on the dangers of cold weather, such is the nature of London's narrative style. But this is entirely appropriate given London's naturalistic bent. The man is an intrinsic part of nature, and so his forlorn struggle against the elements must be presented in the same way as that of any animal.