Yoga and its philosophy, a mystery yet unveiled ?

 It is believed that Yoga thrived in the Indus Valley civilization, one of
the cradles of civilization in north-west of Indian subcontinent.
  But possibly its first practices dates back to early Neolithic age and it is
guessed that these practices had some affinities with prehistoric rituals as
Shamanism, some sort of witchcraft for healing. So the origin and development
of Yoga is still unclear. Even Hindus cannot claim that Yoga belongs to their
religion because its origin and its development predates Hinduism. Instead
Hinduism possibly adopted some of the ideas and practices from the ancient
Yoga.  Also the fact that there are many cults, diversifications and
discernments in Yoga implies that nobody has enough recognition of ancient or
real Yoga as well as its entire history.
 Indus Valley civilization and its major cities such as Harappa and
especially Mohenjo-daro has not been actually discovered until about 1920
when the ruins of the cities and some artifacts were unearthed by
archaeologist. so the history of the cities, where Yoga thrived, is also
unclear.

 But the mystery of Yoga is not just for its origin and formation. The
historians tell us the  civilization  where Yoga thrived culminated at about
late third millennium BC and suddenly demised at about early second
millennium BC, for some doubted and even controversial reasons.

 Findings from the Indus Valley civilization especially Mohejo-daro bears
some implications about the living of their people. Urban facilities such as
developed water distribution networks and sewerage systems tells us that
sanitation and purification was an important part of their living, as it is
also one the main instructions in Yoga.  Those findings suggest more
implications about the living and culture of the people lived in those cities
that possibly unveil more facts about ancient Yoga that may seem weird for
the spirituality of Yoga and even our nowadays norms and moralities. But
these implications remain vague and uncertain, until more findings, if ever
achieved, unveil more mysteries of that wonderful civilization and ancient or
real Yoga and possibly its unknown wonderful philosophy .