The movie Into the Wild could strongly represent the notion of Myths & Heroes. Indeed, a young man breaking free from today's society with its' rules, and therefore accomplishing his dream of living in a wild and free world shows that the young man could be considered a hero. You need bravery, intelligence and very strong convictions to be able to free yourself from all the comfort society offers. The movie also conveys the idea of the noble savage's myth. According to the french philosopher from the XVIII century Rousseau, society has corrupted Man's innocence and it's the people called "savages" who, living in the wild, end up being more innocent and kind-hearted than any civilized man.
Into the Wild could also convey the notion of Progress. The movie shows that progress doesn't only consist of new technologies or advanced civilizations. The young man feels that he is moving forward, progressing, by regressing into a "wild" way of life, where money has no value and where feelings and freedom are all that matter. Progress can sometimes mean to regress to another more simple and pure reality.