Final answer:
Perry's agoraphobia and depression are attributed to his intense fear and mental turmoil, exacerbated by existential threats and an inability to cope with overwhelming inner conflicts.
Step-by-step explanation:
In the context of the provided excerpts, Perry's depression and agoraphobia stem from a deep-seated fear and a profound sense of mental turmoil. This turmoil may originate from various existential fears, like the fear of death and the intense realization of life's fragility, as suggested by the character running in panic to avoid freezing to death. The mental disturbances faced by characters in the excerpts lead to a variety of behaviors, such as neglecting ordinary activities, a ghastly pallor, and a quivering voice indicative of extreme terror. These symptoms reflect inner conflicts and an inability to cope with their overwhelming thoughts and conditions.