Henry Corbin is deep. This book is the conjecture of Hermetic, Zoroastrian, Manichean, NeoPlatonism, and Mandeism expressed through the teachings of Iranian Sufi Masters such as Shoravardi, and Najm Kobra. The idea of internal alchemy find's a language through these stations of teaching and development.
The book begins by directing the reader towards an "orientation", facing a cosmic pole. This orientation is the connection and communication with the internal world of the psyche, labeled as vertical orientation as oppose to horizontal "mundane" positioning.
The orientation thus is turned to the light, at which point the guide of light starts to take a form in the internal landscape. To this landscape is ascribed a structure maintained by a spectrum of photisms.
Each color having a relativity in consciousness, informed emanations of the first order. Tantric Yantras express a similar idea, although contain a different set of colors.
The book also goes deep into the conception of the idea of "seeing" in black light; eo ipso the domain of that which contains light, or rather is beyond light.
I appreciated Corbin's assertion as to the difficulties of any spiritual seeker. The mysteries, that flow from the tributaries pertaining to knowledge of a path. A path that can lead only back to the source, of which nothing can be named or lost.
This book leads one through a timeless visualization of how these ecstatic masters met their true masters' at synchronized positions along the photism spectrums. All along the way there are metaphysically contemplative conjectures of primal and imaginal thought.
This is a hard read, but worth it. And could be a turning point in self realization, if you give it the time it deserves. Like Corbin says "The God you get is the One that you Deserve".