A two-state system is constant.
The existence of mind proves a circle (is conserved).
We are safe (are we safe?).
The black hole is a circle (aka mind and matter).
X and Y conserve a circle.
Yes and no, is, yes and yes (or, no and no).
Conservation and symmetry conserve (must articulate) a circle.
A string of characters, any length, articulates (and conserves) (diameter and circumference of) a circle.
It takes two to make one (and vice versa).