The intermediation between the visible and the invisible in early modern theatre and magic is fitly served by spiritual beings, whose existence was taken for granted by religion, popular culture and perennial philosophy. Animism, defined as the belief in spiritual beings that interfere with humans, helping or harming them, is probably the most archaic and enduring way of accounting for natural phenomena. According to Edward Burnett Tylor, who gave the first in-depth analysis of this phenomenon in Primitive Culture, the basic idea and the model for all the other spiritual beings may have been the human soul facing mortality. Perennial Philosophy treated spiritual beings in the broader attempt to conceptualize what S. Toussaint named the organic participation of the incorporeal to the corporeal. The multiple meanings of spirit and spirits in Shakespeare's plays argue for his vision of theatre as mirror of the time, specifically as reflection of the semantic and conceptual instability regarding these entities in his cultural context.