Final answer:
Franz becomes an atheist in 'Into the Wild' due to the personal impact of Chris McCandless's death, leading him to question and reject his prior religious beliefs.
Step-by-step explanation:
In Jon Krakauer's Into the Wild, the character Franz becomes an atheist after experiencing a profound personal loss with the death of Chris McCandless. The bond between Franz and McCandless was strong, and Franz was deeply affected by McCandless’s free-spirited life and tragic end. This loss challenges Franz's faith to such a degree that he turns away from his previously held religious beliefs. Similarly, in the exploration of atheistic philosophies during the 1800s by thinkers like Karl Marx and Friedrich Nietzsche, there is a general theme of questioning traditional religious beliefs and, in some cases, rejecting them based on a negative side of religious questions.