Into The Wild- Why did Chris McCandless go?

In the book Into The Wild by John Krakauer nobody knows for sure why Chris McCandless felt he had to leave to the Alaskan wilderness. Chris seemed like he was trying to escape civilization and all the troubles that come with it.  Chris came from a well off family and was a very bright young man.  Chris had the opportunity to run a very comfortable modern life, but he decided against that. Living his normal life would have been an easy choice for most, but Chris thought differently. Everyday tasks in life was easy for him but not enough to keep him happy. Chris did not see the world in a positive manner, he saw the negative aspects of it and he hated that no one else wanted to change it.
Towards the end of the book it explains how Chris was effected by learning about his dads affair as well as another son from a different women. He was extremely angry at his family and refused to forgive him.  This led Chris to be very unhappy with the world in general.  Chris probably began to blame society at large for his unhapiness. This is why he wanted to leave into the wilderness and escape the world around him.  He was influenced by reading ideas by Henry David Thoreau and Ralph Waldo Emerson that encouraged the ideas of living in the wilderness.  He believed that the only way a man can be cured is by returning to nature. Based on Chris' Journal it seems that in the end he did find what he was looking for in the wild, but he wanted to return to civilization, and was blocked by the obstacles of nature so he could not return.