@cicerone imposter,
I dream. I have vivid dreams. I had a dream a view nights ago where I believed 100% that it was real. I even thought back to other dreams I had had and concluded that this was real.
However, I woke up. I found out that it was not 'real'.
I have had other dreams where I woke up in my room and did things and thought it all to be real...then I woke up for real and found them out to be false.
Now, I present my subjective experience which I know I cannot accurately convey to you.
But regardless, it is something to inquiry about. Because I thought and I believed.
And as Descartes said, "I think, so therefore I am."
That is my question and that is the reason for the quote.