From a philosophical perspective, the universal belief in Satan and evil demons is based on the need for an explanation of the enormous quantity of moral and physical evil pervading human existence for our entire history. The manifest presence of suffering in the lives of all is a fact which cannot be ignored nor denied. As the search for meaning in existence inevitably develops, explanatory systems emerge to cope with fundamental existential questions.
One response is the postulation of the existence of a being or beings who create and/or personify evil. While the figure of the Christian Devil, Satan, most clearly exemplifies the anthropomorphic concept of evil, there are numerous examples of gods or spirits from widely divergent cultures who share some of his most prominent characteristics. This shows that the concept of "the Devil" far from being a phenomenon with origins specific to Christianity, can be found in various forms throughout history, regardless of time and place.
Psychologically, demons may well be a projection of ourselves, the worst part of our nature or the most feared part of our own nature.
