a body, polygon or form
is proclaimed symmetrical
when split along an inner axis
halves in two shapes identical

every artifact you see
can be it itself symmetrical
with the single exception
of objects you can't see at all

time is the best example
although very visible
when you come to think of it
is nohow symmetrical

between the past and future
runs an axis called today
look at them juxtapositioned
a constraint comes into play

two parts can only be symmetrical
when they can mutually exchange
once future however turned to past
it can never more rearrange