In the Islamic religion, it is believed that another species exist along side humans. They are called Jinis (yes the popular Jini in the bottle of Aladdin is one of them). They are more than just a myth and all Muslims believe in their existence but can never prove it just like they believe in the existence of angles but they can never prove it.
Anyway, these Jinis have the ability of disappearing and to change form. Their abilities are much stronger than ours but they are really stupid. They like to claim to be Gods and often are mistaken for gods for their unbelievable power. They live a lot longer than us humans and they can penetrate a human body (The movie " the exorcist" building on the popularity of this phenomenon). In old ages they were able to peak into the future and hence the claim that some people can see the future threw spirits. Magic can also be mastered using their power. They will tell you the future and give you magic abilities if you commit an act of religious loyalty such as a sacrifice as in giving them godly rights. Of course there's only one god and these creatures are just creatures nothing more, despite the power they wield. And if you do pledge loyalty to then as gods which they're not, then you would be damned.
Their existence cannot be proven yet, but for those who would doubt it, go to an old mansion or an old wreckage (their usually habitats) and try and sleep there all threw the night. You'll feel a very strange fear that you just can't explain. And who knows, you might just get a chance to hear or even see one in the form you most fear.
This is nothing strange to third world countries as there are a lot of abandoned houses and creepy places no one would dare come close to.
And the question just has to be asked, why are witchcraft wide spread and there are books about it. Are they just a legend?
Now, if you don't believing god than all the above is crap. But if you do and you are of the heavenly believes (Jewish, Christian, Muslim) you would know that there is more than what meets the eye in this world, we just have a problem accepting it, just like the poets of the 18th century had a problem believing Newton's claim that he made laws for motion!
P.S. I had you going didn't I, LOL (no just info that I believe, you can take it or leave it)