As writers we are expected to write what we know and what we do not know. Think about it, everything our characters have gone through or will go through, have we gone through it? Not always.
So how we do write what we have never experienced?
How do we know how they feel if we have never felt what they feel?
How can we create what we have never seen?
The mind is a powerful tool, one that can do exactly this... Create.
Now sometimes we write what we do know, we feed off of emotions we have felt or feel, which leads to a very heartfelt piece, which is wonderful indeed.
It just amazes me how writers can write something that they have never seen, experienced, or heard.
How we escape this world, ourselves and everything normal and dive into a place created by our imagination and our deepest inner-selves is something special that we should all cherish and love.