“There is a spiritual sky, where there are innumerable spiritual planets and innumerable spiritual living entities, but those who are not fit to live in that spiritual world are sent to this material world. Voluntarily we have accepted this material body, but actually we are spirit souls who should not have accepted it. When and how we accepted it cannot be traced. No one can trace the history of when the conditioned soul first accepted the material body.” (Shrila Prabhupada, Easy Journey To Other Planets, Ch 2)