Second, why didn't the female doctor tell him the cause of death. Why didn't the mental patient tell him the cause of death. The online explanation is too far-fetched.
Third, about the meaning of life: maybe this is what the film is about to say. "Death always comes when people don't want to die," cherish what is in front of you, no matter how bad your life is, at least you are alive. The last sentence of the film, how long do you have? It is for all of us.
Finally, as to whether it is better to live lucidly or in dreams, I personally think it is a question worth exploring.
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