It is not enough to say that the symbol is a sign which suggests something mystical. The symbol must be a machine or engine for the generation of magical power in its own way, not in any way which depends on the mere mind of the practitioner. Voudoo must be a science of success which works for every mind, and not because of mental attitude alone . . . Voudoo is not psychological, it is metaphysical and physical.
-- Michael Bertiaux (qtd. in Kenneth Grant's Hecate's Fountain)