How do individuals construct identity through their actions, values, and beliefs?

The elusiveness of identity, or of truly understanding someone’s identity, is a theme both explicitly and implicitly present throughout Into the Wild. Krakauer spends about three years putting together first the article on Chris McCandless, and then this book. He talks to almost anyone who met McCandless, even fleetingly. He follows McCandless's trails, reads his journals, even reads the articles he wrote for the student paper at Emory. Krakauer also feels he has an extra level of understanding, because he was much like Chris when he was in his twenties.

Yet even with all of this, at the end of the book, Krakauer acknowledges that McCandless’s presence remains elusive. As closely as he may have studied him, as well as he has come to “know” him, there are a few fundamental questions which no one, not even Chris’s parents, can find a satisfactory answer to. Most important of these is how someone so compassionate, kind, and intelligent could have ended up devastating his parents, and all of those who loved him, so profoundly. The ultimate inability to truly know another person is thus at the heart of Into the Wild.