The Nice Equation

There's a secret to this world,
Rumored to have been captured
In a single formula
Half a line long, elegant,
Tautological, precise,
Yet so vastly general
As to apply to all things.

Or there is no such secret,
Only that neat formula
Summing exactly nothing
But so, so beautifully
That one feels the solution
Deserves some brutal riddle
To heroically resolve.