If you think this Universe is bad, you should see some of the others.
Out beyond our world there are, elsewhere, other assemblages of matter making other worlds. Ours is not the only one in air's embrace.
In science fiction, you can also test out your own realities.
A few dud universes can really clutter up your basement.
It's a very salutary thing to realize that the rather dull universe in which most of us spend most of our time is not the only universe there is. I think it's healthy that people should have this experience.
Writers of all things speculative have played in alternate and parallel worlds for a long time - everyone from Stephen King to Philip Pullman to Tanith Lee - and it's an obsession that likely isn't going away any time soon.
We could imagine all sorts of universes unlike this one, but this is the one that happened.
One of the things I love best about Marvel is the 'What If?' factor; being able to just say, 'Today we're going to explore a world where Magneto and Emma never gave back the X-Men. Or a world where Mary Jane shares Peter's powers.' So being able to do that is just super exciting.
It is easy to slip into a parallel universe. There are so many of them: worlds of the insane, the criminal, the crippled, the dying, perhaps of the dead as well. These worlds exist alongside this world and resemble it, but are not in it.
