Phong experiences that he is living in a dreaming world where he meets his neighborhood people and the place where he resides is actually not existed. This kind of feeling would lead to a diagnosis of derealization.
Mental illness is a state of an individual's mental condition where his/her emotions, thoughts, and behaviors are completely changed. It can be due to excessive stress taken by an individual.
Derealization is the state of an individual's mindset where he/she feels to be completely detached from their daily life. The people around them seemed to not really exist. Around half of the living population felt this kind of state one's in their lives.
Therefore, derealization is the state of living in a dream where the real existing people seem to not exist.
Learn more about the mental illness in the specified link:
https://brainly.com/question/933852
#SPJ1