It’s fun to think of a different reality. We’re pretty used to this one. We know that when we drop a pencil on the ground it’s going to stay there, because of the laws of gravity. We know that if we bend our arm a certain way, it will break, given our knowledge of our own bodies. We know that if we try to breathe underwater, we will drown. Boring stuff, I know. 

But imagine a world where you drop a pencil and it just floats there in the air next to you. Where you can bend your arms backwards and forwards and every way possible. And imagine a world in which we could breathe underwater. I would make friends with so many fish. Heck, I might even spend most of my life down there if they would have me. This is why we turn to science fiction, to help us imagine this.