The guy Max saw in the subway, who's reading his paper one scene, and another is singing a song, is that guy really there or is Max seeing things? And that other guy that stands near pole, and his hand is bleeding, is that guy even real or no? Wouldn't a person die from putting a drill to the head? How is he still alive? What causes Max to have continue shake of hands, and was he having seizures?
"It's up to you to decide" ..its not that kind of movie. The scene in the bathroom with the drill is called trepannig. The final scene is him sitting on the park bench unable to answer the math question because of the trepanning, while gazing up at the tree in peace