How does London use the man and the dog to illustrate the difference between instinct and knowledge?

Throughout the story, London compares the man's knowledge to the dog's instincts, and the dog's instincts seem to be superior. The man knows that it is cold. Unlike the dog, he can read a thermometer and give the precise temperature, but he does not understand the significance of these facts. London writes, "He was quick and alert in the things of life, but only in the things, and not in the significances." Despite knowing the temperature and despite knowing about frostbite, he still chooses to travel alone in these harsh conditions.

The dog, on the other hand, has no precise knowledge, but its instincts tell it that it should not be out in the cold. If it weren't for its obedience to the man, the dog would seek shelter. Once the man dies, the dog's instincts tell it to go to camp to find others.

Interestingly, London writes that the man's blood has instinct and, like the dog, it attempts to flee the cold. London writes, "The blood was alive, like the dog, and like the dog it wanted to hide away."