Various ideas on how the universe appeared and develops, were in Indian
tradition related to mythic, religious, or philosophical ideas and contexts,
and developed during some 3.000 years - from the time of Vedas, to Puranas.
Conserning its appeareance, two main ideas were presented. In one concept it
appeared out of itself (auto-generated), and gods were among the first to
appear in the cosmic sequences. In the other, it was a kind of divine
creation, with hard work (like the dismembering of the primal Purusha), or as
emanation of divine dance. Indian tradition had also various critiques of
mythic and religious concepts (from the 8th c. BC, to the 6c.), who favoured
naturalistic and materialistic explanations, and concepts, in their cosmogony
and cosmology. One the peculiarities was that indian cosmogony and cosmology
includes great time spans, since they used a digit system which was later (in
the 13th c.) introduced to Europe by Fibonacci (Leonardo of Pisa, 1170-1240).