We do not incarnate aimlessly or randomly, even though nearly all people (including the believers in reincarnation) have no idea why they are here. We incarnate for a very real purpose that leads to our eventual liberation. The idea that our life is something for us to fiddle around with and use for whatever small-term goals our deluded minds and egos can come up with is a terrible mistake, and results in wasting lifetimes. It is an invitation to more and more suffering and frustration. Finding out our purpose is not really difficult. The Bhagavad Gita presents the full picture.
Human birth is not easy to attain because we cannot be conceived and born if both parents are not compatible with our karma and a match for our entire psychic background. This is not common, so a person can wait decades or even centuries to find parents who can produce the body needed to manifest his karma. Therefore it is a great shame that when we do get human birth we waste it in pursuing little ego-goals, leaving aside the Great Goal.
Those who have recall of their pasts lives, including the experience of birth and death in those lives, say that it is easier to die than any other phase of life. Death itself is not pain, but release from pain, for entry into the astral world is less confining than earthly birth. To die is to be delivered, at least for a while.
Human beings often behave like animals rather than humans, reverting to the ways they followed in their lives before reaching the human level. Being in a human body is no guarantee of true humanity.
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