Gift Horse

What's bad? What's good? Its often hard to say.
One man's bane is another's sturgeon roe.
While hunting pigeons, Joesph heard a neigh.
He stalked, then snared a horse. which he brought back
to show his family. "It's so good, Joe!"
they cheered, and then proceeded to attack

three kegs of beer. Well, Joe got drunk and raced
his horse and fell beneath, breaking his arm.
"it's bad! It hurts like hell", he yelled. His taste
for steeplechase now at a low, the King's
recruiters came to take him from the farm.
As armies have no use for men with slings,

they left him there. "Hurray" his mother whooped,
"It's good!" But sad for all, luck does have laws.
His horse bumped up against him as he pooped,
and Joe fell in the crapper's trench and died.
As much unseen upholds effect and cause,
like yin and yang, each opposite's implied.