Shaking is a complicated thing—for me, at times, all-consuming. I’ve had a paralyzing fear of the kind of uncontrolled internal terror and shaking that I’ve experienced with panic attacks. Then there is the full-body vibration, like electricity coursing through me, during bodywork therapy that has not only evoked uncontrolled noises but eventually numbed my hands, making me feel as though my palms and fingers were the size of baseball mitts. This was good, my therapist told me. Some people never achieve this flow of what Wilhelm Reich, the father of mind-body medicine, referred to as “orgone” energy (a life energy flowing through the body that affects and is affected by one’s emotional state). In my four years at healing school, I frequently went into full-body shakes. I was feeling my terror. Was this good? In orgasm, the shake is delicious. A shaman colleague teaches transformative dancing “shaking medicine,” which African Bushmen have used for centuries to experience God.

And then there’s being shaken—at its most extreme, the kind of shaking one animal uses to try to kill another.

I was thinking about none of this one frigid morning in Central Park four years ago. I was simply feeling mellow, standing among my friends on Cherry Hill, a slope overlooking the Central Park Lake where people gather with their dogs to let them play off-leash in the early morning. The only shaking going on was from the cold, and, bundled in parkas and scarves, most of the people were clumped in chatty groups, hardly noticing their frolicking dogs.

At the bottom of the hill, a rambunctious little Yorkie puppy was barking and jumping, inviting a shy toy poodle to play. The poodle was reluctant, but the Yorkie was insistent. The poodle’s owner was watching, trying not to interfere, maybe hoping her dog might become more social. I too was watching, when seemingly from out of nowhere a large black blur silently flew at the two little dogs and pounced. For a slow-motion moment, all human sound ceased. There was no growling from the black dog…nothing except the terrified squealing of the Yorkie, then the terrified hollering of humans—the Yorkie and poodle’s women—as the big dog stomped, then grabbed the Yorkie by the scruff of her neck and shook her like a rag doll.

It was a primal act that we humans instinctually recognized: the shake to kill. The owner of the big black female dog, a man in his 20s or 30s, tackled her. The chic Yorkie’s owner dove, arms outstretched like a baseball player sliding into home, shrieking and rolling. The man punched his dog, who dropped the Yorkie—quickly swooped up by the woman on the ground. And the rest of us—an unwitting audience—what did we do?

At the conclusion of this battle of life and death, we instantly unfroze, reverting to our dominant character roles. The mother figure among us, the petite woman with the Poodle, suddenly appeared gargantuan and, like a Marine sergeant, marched both the injured Yorkie and the now hysterical person to the vet. The man with the big black dog collapsed on the ground beside her. I approached with pen and paper and suggested we all try to breathe as he gave me his contact information for my friend.

“She never did anything like that before,” said the man, staring at me blankly. I forced myself to breathe—again and again. Because underneath the quiet and shock and our uncontrollable shaking was a palpable possibility of rage—for someone to snap, lash out, blame, defend, accuse. Instead, we all breathed. We allowed the shake to flow without action. Then, reverting to the habit of resigned New Yorkers—who regularly witness bad or cataclysmic occurrences and, realizing there is nothing we can do, walk on—everyone but the man and I dispersed. And after he gave me his information, we too went our separate ways.

This was my first experience of an almost-worst outcome of shaking: death. When I fear shaking, what I fear is coming undone—being the rag doll in an internal big dog’s mouth, being murdered from the inside out.

Since the economy imploded and mass shootings exploded, I believe that I have a lot of company. I believe that, whether we’re aware of it or not, increased shaking has become almost normal. Perhaps we’re all afraid of being murdered from the inside out, and maybe, through projection, we’ve flipped this, creating an outer dramatization of that scenario. Projected out, what we dread most is being acted out in our culture. And maybe on some level, it’s the natural course of evolution.

Shaking is a response to the disruption of everything we’ve known, preceding change. Shaking destroys land bodies…which eventually regenerate into a whole new scape. We shake when we die, as the life energy departs in another form. And sometimes we are driven to it to try to quiet babies when their life noise becomes too much. Shaking happens when we are overwhelmed.

But shaking is also the energy and essence of healing—healthy cells move. Shaking is the motion of life. Shaking is the movement of fear and rage and orgasm. It is a killer instinct and the instinct to live. Since 3000 BC, when the Chinese began to understand and direct chi, to 2014, when we use the vibration of magnets to help bones heal faster and nuclear fusion to potentially empower or obliterate ourselves, we have understood the positive and negative power of this movement.

How to live with something so complicated?

I’m working on allowing it. After all, what else is there to do? If I choose to, I can house and tolerate the shake, knowing when to act, knowing when to witness, knowing that all this movement—it’s just life.