The Prophetic dreams
Though there is a scientific-grounded theory as for dreams phenomenon there are still people who make their questions about what dreams are and where it come from. Most of them recognize dreams a something mysterious and supernatural and some of them follow the scientific theory and don't in mystic of dreams.
Indeed, it is common that a dream is just a product of our imagination and subconsciousness. Scholars say that those are results of mental problems people have. Say, there is a problem and one can do nothing in order to get rid of that problem and he can also do nothing in order to solve that problem. Though, it bothers him or her everyday.
And the dream he or she will have is a result of that problem being unsolved. It is all clear but how can they explain the fact that people see prophetic dreams? Indeed they see those, they state that those become real with some lapse of time. It is not about dream-books and meaning of every single thing you see in your dream, but it is about dreams people see their future in.
There are a great number of people who state they have seen some event of their life before. Sure, it is hard to believe in it though researches (held in order to realize what the deal is) shows that people are not lying and that they telling truth. So, it is possible for people to see the tiny something from their future in prophetic dream, though one can't make those dreams come t him or her.