In "To Build a Fire," how does the man in the story allow his pride to interfere with his survival?

In "To Build a Fire," the primary reason for the man's death is not the cold itself or the lack of a fire, although these are the most direct and empirical reasons. The real reason is his pride, in that he never should have been out alone in the first place. 
We can immediately see elements of pride—or at least naive confidence—in the man's character. He is mentioned as being new to this country, and so to him, 50 degrees below zero is just a number; he fails to understand the way in which this mere number will affect the nature of life itself. 
As the man reflects on his journey, he frequently thinks back to "the old man from Sulphur Creek," who we may assume from context clues was a wise and helpful person who learned the practical rules of life in the Yukon. One such memory implicates pride as the primary character's weakness.

The man had been very serious when he said that no man should travel alone in that country after 50 below zero. Well, here he was; he had had the accident; he was alone; and he had saved himself. Those old men were rather womanish, he thought.

Following his turn of bad luck, the primary character begins to think on how the old man might have actually been right, and indeed, his last words are "you were right, old fellow, you were right." In retrospect, it seems like a ridiculous thing to have taken pride in, when the presence of another person probably would have saved the man's life. Furthermore, there was never any real reason given for the character to have been traveling alone; it seems as though he may have simply done it to prove that he could.