Your dreams and imagination evolved as a view into another universe. As with the current beliefs, you cannot decipher technical information – no words in books, no details of how devices work, so even if you can describe things you see from another place, you could not reproduce a working version.
Now how do you convince others that the things your are seeing are really happening without being labeled insane? And how could you use this information to benefit yourself or others? Take a peek into the multiverse to see how other versions of yourself have solved these problems…
(Yeah I don’t know of any other suitable communities either, this seemed the most appropriate.)
In my hypothetical this would be the reality of everyone. Apply it to the world you know, but where you believe your imagination/dreams/whatever are creating new ideas, what you are really doing is seeing the possibilities of other realities. Except for that change, everything else is exactly as you know it now.
The way I see it, we would never know if the imaginative ideas that come into our head develop from the random crossing of neural pathways, or from a peek into a slightly different world. Maybe that peek is enough for you to piece together your own solution, but even in that case did you really just invent something or did you just happen to view a reality where a random set of occurrences caused something happen and it only feels to you as if you thought of it. The whole point of this thought experiment is that we really don’t know where our imagination comes from.