Should a Mule Become a Horse?

"They said no matter how far a mule travels it can never come back a horse" (Junot Diaz)

How far must
a mule travel
to come back 
a horse?

Would this journey 
require
evolution?
adaptation?

Is it better
to be a horse
than a mule?
I'm not so sure

since my 
stubborn
disposition
helps me

keep a routine
even when
what seems
apocalyptic

closes the road.