Look into the kabbalah, the free-masonic order, Illuminati, new world order and so on...
("Freeman Fly" among others on Youtube talks about these topics)
Parts of those groups seem to engage in demonic rituals (including human sacrifices of virgin women and children) with the purpose of calling forth evil entities from other realms that then would benefit them.
One of the perks ought to be greater insight into the world as it is (present) and can/will be (the future).
As you can imagine not much of this theory can be proven...