Antithesis

Those who can, drink,
those who can't, preach,
those who can, clean
those who can't bleach.
Those who can drink bleach
cannot thereafter think or preach
the virtues of cleanliness of thought,
nor can they confess
the drunkenness
which caused this mess.

The moral of this story isn't clear,
except you cannot clean your mind
with bleach, but have no fear,
though there is much that
is reduced by copious drinking,
including man's capacity for thinking,
his thoughts wouldn't often be so impaired such that
he might believe he was made of asbestos
and able to withstand a pint of Domestos.