This anatomical symmetry is deceptive when reflected. Gravity bends time and space. Like light, time is made up of particles. Particles have mass. Mass has weight.
Time has weight and therefore velocity.
That's why the older you get, the faster time progresses. But I digress from my discussion of the symmetrical properties of the number two. Human symmetry, though more than skin deep, is not total. We have but one heart, and it is not symmetrical, but located to the left of center. Unless we are a pair of mirror twins, in which case it may turn up on the right.