The Dark, for awhile.
And my dreams. For some reason i would have a nightmare almost every night during my early childhood. I can still remember some of them.
Nowadays there is the fear of someone breaking into my home; of course I suspect that almost everyone who lives in Jo'burg has that fear
"The good Christian should beware the mathematician and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of hell." - St. Augustine