Dreams seem to have a re-creational value.

You are the dream. You are everything and everyone in the dream. You set the plot. You are the audience watching the performance on the stage. You are yourself and all of the actors and things.

If its good you enjoy it. If its boring or scary you change it to whatever you prefer. If its especially interesting you can get up, go do whatever, and resume when you get back to bed.

There may be times when external factors affect the dream, but you are still the dream.

If you watch closely you can see that the laws of logic work smoothly with the non-logic of imagination, like a magical world might function. The physical laws of the waking world do not dictate as they do in the waking realm. For instance, if you drive you car into a lake it is a boat. It just is, without conflict with logic or calculation.

One might wonder if the corpus callosum is an engineered filter or control mechanism to keep humans from exercising full spherical potential in waking mode. Perhaps a device that only allows a very limited interaction of logic and ability to create, with logic dominant.

One might also wonder about black sleep which seems to have a sense of cover for theft of some type.

Maybe dreams are a re-creation of what a free waking life should be.