71 You only live once

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You only live once

You only live once
Or so the saying has it.
Believers think the opposite:
We die but only to be born again
In some far, far happier land than this.
Not all that difficult to think of one of these!
But this is only true of those who were not sinners
During their one and only life spent toiling here on earth.
For those who erred then failed to repent, their reward is more
Varieties of punishment in hell than you and I have had hot dinners.
Others, not content with the idea of only one existence post mortem, 
Think that, post death we come round and round again ad infinitum, 
Immortal souls to be found in all sorts of problematic incarnation:
A sunflower or an earwig or whale say, by way of illustration.
Some types of existence might prove to be enormous fun,
All those days out in the fields, just basking in the sun!
But what if you’ve been reborn the innocent prey 
Of some lurking predator, eaten your first day? 
Or you’ve come back as a tiny piece of krill 
To be hoovered-up and instantly digested
Before you’ve even tested the water?
You can but hope things get better 
Next spin of the Great Wheel.
There’s much to be said
For the proposition 
In the title.