The Conscious Mirror

A textbook on the psychophysics of consciousness, from over 2000 years ago, somehow survived into the 21st century world, hidden in dusty bookshelves of ashrams and universities, disguised as quasi-religious, metaphysical nonsense.
'Tripura Rahasya' is a book about three states of consciousness - wakeful, dreaming, and dreamless sleep. The word 'Tripura' in the Sanskrit language means 'Three domains' and 'Rahasya' means 'Mystery'. So, someone wrote a book called 'The Mystery of the Three Domains', a few millennia ago.
It was written around 250BCE by an unknown author called Haritayan, possibly a Professor at an ancient Indian university. It was probably a 'taster' course for applicants.
Enjoy your journey into that alien world....