The man is optimistic when he stops for lunch. He has made good progress on his journey and feels confident that he can make it to camp before dark. But when he stops for lunch, he is surprised by how cold it is and how quickly his fingers go numb when he takes off his mittens to pull his lunch out from under his coat. He is even a bit frightened. He remembers what "the man from Sulphur Creek" had said about the cold and admits that it shows that "one must not be too sure of things." It is only then that he realizes that he has forgotten to build a fire.
The fact that he overlooks such a crucial factor says much about his state of mind. He is not thinking clearly, if at all, about his predicament. In this, he is contrasted with the dog that accompanies him. The dog knows instinctively that it is too cold to travel, but the man, lacking even this instinct, is not even as intelligent as the dog. Once the man builds a fire, his fear about the weather subsides and he begins to feel comfortable about his situation. He even takes some time, after his meal, to smoke. When he leaves to return to the trail, it is with a false sense of confidence. It is not long after this that he falls through the ice and gets wet to the knees.