Good question. Why didn't I think of it ? May be someone who is
blind should answer this question. To know what they are dreaming,
may be the person can draw on a piece of paper what they see
in their dream and whether it matches with reality. If
what they dream match with the thing in reality, then I wonder why
they can dream of something they have not seen. Amazing. Don't tell
me blind people cannot draw. If can't draw, may be they can
describe.
I like the way you think!
I don't think they would be able to draw things that will be
exactly like reality, but if they've tried to familiarise
themselves with shapes of different objects etc. through touch,
then perhaps they can draw something that would be close to what it
is exactly.
Wonder if there's any research or stuff on the net on
this...