- As of yet Unknown
As of yet, no known Signamancer has been introduced, but apparently Transylvito has some.
Parson a possible Signamancer
Real World References
The Signamancy is highly reminiscent of Plato's philosophy, espoused in the Allegory of the Cave, in which Plato explained how perceived reality is nothing more than the shadows of the true reality. Also, highly analogous to Enlightenment/Awakening in general  particularly in light of it being an aspect of Hippienism.