Question: Why do we dream?

Nicolas Labrosse answered on 12 Jun 2017:

We dream because our brain needs it to process information. But as I’m not an expert, please don’t take my word for it. Instead, I’ll give you now a dreamer’s answer(*)…
We dream because we can. We dream because without dreams you can’t develop. I’ve actually just seen tonight a slogan that said something like “Dreams come in a size 2-3 times too large so that you can grow comfortably in them.” It’s not the exact quote and I didn’t take a note of it, and can’t find it again… (Perhaps I’ve dreamt it!)
The brain is a fascinating thing and if I had been a scientist not working in astrophysics, I would have liked to work on the brain and understand it better.
(*) I don’t mean that brain experts aren’t dreamers or can’t give you a dreamer’s answer! On all accounts they can actually answer that question better than me!