Its Sorta like the idea that the only thing you can prove is your own consciousness, so you will never know anyone else actually exists.
I kind of have a problem with that. Where are the hallucinations coming from? What's the source? Plus if we wanted, we could determine why every single person did what they did at every point in their life, along with other living creatures. And how did you perceive things like complex works of art before you understood even on a basic level how they were made? We know how they were made within reality, yet the one consciousness was still able to perceive them before they knew anything about it. And it seems that the hallucinations would have to at least make sense within the context of the false reality they're in. I think the vessels of God thing is more likely, though I don't believe that either.
It's (officially) called Solipsism, and the fact that there are a ton of people around the world who come to the same conclusion of "only I exist and everyone else is a dream" make it seem oh so improbable.
Maybe â€other people†are solipsist only because God wants you to be aware of the concept at some point.
It just seems , for me, so untrusting of the human experience to think only yours is real. It's an interesting philosophical discussion though.
If God has infinite power and resources he can easily create billions of universes, one for each person, to be each person's private Heaven and Hell. Kind of like a galactic or spiritual version of The Truman Show.