Dreams? My theory on dreams?
Oh dear, this might take a while.
I think that dreams reflect whatever is on our mind. Anything. Ranging from a particular emotion we're having at the time to a complex situation that's affecting our lives.
Dreams can also reflect memories, even ones we've 'forgotten'. I know I have a few memories I dreamt about, and when I talked about them later, my mum, or a relative would go 'Oh, you're talking about that time when and such and such happened'.
So far, I've explained that dreams pretty much reflect whatever is on your mind, and often bits and pieces of a number of things, such as a location, people, emotions, fears and wants, coming together to make something that appears to be a complete mess.
In some cases, things would represent something, something that the mind already knows and has come up in our subconscious, but since it can be so dodgy or whatever, it ends up being symbolic, so it's up to our concious to figure it out. Like a dolphin might represent someone who is playful or happy.
Essentially, dreams reflect what we know.
But then I expanded on this theory, and the rest is something I'm still thinking about.
Spoiler:If dreams can reflect memories, then what about the future, or memories we have yet to have? It could be possible, and this is simply my own, crazy theory, that we already know what the future might hold, and our dreams can reflect that, BUT knowing the future isn't always a good thing, and with some people, attempts to 'dig' deeper into the dream can result in pain, a sort of defence system I guess, to prevent us losing our minds in time itself. The memory hasn't actually occurred yet, but it will.
Once again, my own crazy theory that even I'm not sure about.