How are the instincts of the man different from the dog's instincts?

The dog's instincts are natural, they're inbred. A dog understands it's too cold and yearns for warmth; dogs will naturally protect their paws and bodies from the cold and ice, and dogs understand when they're facing danger and will withdraw or fight.

In this case, the man is too prideful and inexperienced to even think about his own instincts. He doesn't listen to the advice of others, he doesn't pay close enough attention to the cold, and he over estimates his own abilities in regard to what mother nature throws his way. It wasn't about instinct..... it was about doing what he wanted to do and failing to listen to those who knew better (this includes the hints given off by the dog's behavior).