A dome-shaped muscle that divides the trunk in two. Through its openings pass the aorta, the esophagus, the vena cava — and, most importantly — the vagus nerve.

With each deep diaphragmatic breath, the diaphragm massages the vagus nerve — gateway to the parasympathetic system. When it moves freely, your body receives the signal that it is safe.

Your autonomic nervous system runs in two modes. Meditation requires the parasympathetic. Most people try to meditate while still in sympathetic.

The brain network that runs when you're doing nothing specific — daydreaming, ruminating, worrying. The mental autopilot. When you anchor to the body, it deactivates.

When you are present, the prefrontal cortex activates and the DMN drops. Each return to the meditation object is one rep of the muscle that reduces the DMN.

Ritual turns a sporadic practice into a state the organism seeks and defends on its own.