Precious yet often
wasted is this Human Opportunity!

The Blessed
Gotama
Buddha
once explained:
Bhikkhus
and friends, imagine a single floating ring drifting
randomly in the great
oceans!
Imagine
also a blind turtle swimming about, which surfaces only once every 100 years...
What do you think, Bhikkhus, would that blind turtle by chance often dive
right up under
this randomly drifting single ring and insert its neck into this
half meter wide
hole?
If it
ever
would
happen at all, Sir,
it would only happen after an incredibly long time!
Yet,
Bhikkhus
and friends,
I
tell you, that this would happen sooner, than a fool, who has
fallen into the lower levels of existence, would again regain this rare human
state...
Why so? Because down there exists neither behaviour guided by the Dhamma,
nor any
honesty, nor any morality, nor any kindness, nor any opportunity
for meritorious
action.
There prevails only this evil: beat or be beaten, eat or be eaten, cruel
merciless killing
and voraciously swallowing up of any weak being. Why is it so
wildly primitive
there?
Because, Bhikkhus, down there nobody have understood these
4 Noble Truths!
What
four?
1:
All
this
is Suffering;
2:
This Greedy Craving
is the
sole
Cause of all Suffering;
3:
No
Craving is
the
End of Suffering;
4:
The
Noble 8-fold Way Ends all Suffering,
Therefore should an effort be made
right NOW to understand these
4 Noble Truths!

Comment:
Despite
the fact that downfall to a subhuman level is a common event occurring at almost
all deaths (>97%),
many beings
think that the downfall either not happen to them (sic...!),
or that it
does not happen at all, because they cannot remember their last nasty
surprise...
Learning anything about cause and effect is thus effectively disabled
by transmigration!
The very same mistakes are thus repeated, life after life,
in an almost endless tragedy!

The Blind Sea-Turtle Simile...
Source (edited extract):
The
Grouped Sayings of the Buddha. Samyutta Nikāya. [V:455-6]
section 56:
Saccasamyutta. Thread 47: The Ring and Blind Turtle ...