There is a mathematical equation,
known as Euler's identity,
that is considered quite beautiful:
eiπ + 1 = 0
This pinnacle of mathematic perfection
relates five of the most fundamental constants
(e, natural growth; i, the imaginary; π, circular
periodicity; 1, unity; and 0, nothingness)
in four fundamental operations
(exponentiation, multiplication, addition, and equality).
This relationship, so poetically called an identity,
is one particular case of Euler's formula,
with no true use unto itself.
This curious beauty, artefact
of our own imperfection, is
an identity of universal truth.