The Illusion of Self

We think of ourselves as separate beings isolated from the rest of the world, with our skin forming the barrier between inside and outside. This sense of separateness runs deep within the human psyche, guiding our thinking about such fundamental issues as being, life, and (particularly) death. Among Westerners, the notion of isolation extends outward to embrace humanity and exclude the nonhuman world; in this conception, humans exist outside, usually above, nature. The end result of all this externalization is billions of “skin-encapsulated egos,” each of us consumed by thoughts of furthering our own ends and protecting ourselves from the outside world.

But what if we are not separate at all? What if we are fully immersed into the ebb and flow of everything around us? Would such knowledge change how we think and act? I’m not certain about the answer to the third question, but there’s now little doubt about the first two. Scientific insights over the past several decades mirror much older insights derived from a variety of wisdom traditions. Despite its near ubiquity, we can state with confidence that the notion of a separate self is largely illusory.

The most obvious challenge to the concept of separateness is our need to consume air, water, and food. At what point did your last breathe, sip, or bite cease to be part of the outside world and become you? The truth is that we constantly exchange matter with the outside world, replacing every atom in our bodies every seven years or so. And your metabolism is intimately linked to Earth’s metabolism. Energized by sunlight, life converts inanimate rock into nutrients, which then pass through plants, plant-eaters, and animal-eaters before being decomposed and returned to the Earth. Humans fit into this amazing planet-scale metabolic system as major consumers of plants and animals. Isolation from any aspect of this metabolic flow translates to death.

If all that isn’t enough to dampen your sense of separateness, how about the fact that the body you identify with consists not of one life-form but many? Your mouth alone contains more than 700 distinct kinds of bacteria. Carving out a variety of roles over every square millimeter of tongue, teeth, and gums, many of these microbial partners serve as armed guards, improving health by fighting disease-causing bacteria. Others can cause dental cavities if you don’t brush. Your skin and eyelashes are equally loaded with bacteria (no matter how long you shower) and your gut has a bevy of bacterial sidekicks (on the order of another 500 varieties) that are essential to converting food to useable nutrients. Although this still leaves several bacteria-free regions in a healthy body (e.g., brain, spinal cord, blood stream, etc.), current estimates indicate that, of the 10 trillion cells that compose your physical self, 9 out of 10 are not human cells. This means that your body is home to more lifeforms than there are people on Earth, or stars in the Milky Way galaxy.

If your bias is to count genes instead of cells, the truth of the matter becomes even more stark. You house about 30,000 human genes, versus about 100 times as many bacterial genes. In short, depending on how you make the calculation, you are somewhere around 1-10% human, and 90-99% nonhuman (1). A large-scale, five-year research effort called the human microbiome project (HMP) is currently underway (2). Five main body areas are being targeted in the HMP -- skin, mouth, nasal cavity/lungs, vagina, and gut -- but the goal is to identify and characterize all the microbes inhabiting the human body. If you’re immediately inclined to regard these multifarious bacterial hitchhikers as freeloaders, or even parasites, keep in mind that these trillions of microbes are indispensable to your health, helping to regulate not only your physical well being—digesting food, processing vitamins, keeping out bad bacteria, etc—but perhaps your mental and emotional vigor as well.

And just in case you attempt to cling to some kind of special status for your human cells, it turns out that even they are likely the result of ancient evolutionary mergers with bacteria. Each of your human cells contains a “mitochondria,” a membrane-enclosed “organelle” that is responsible for generating most of the cell’s energy, as well as such activities as cell signaling, growth, and death. Hundreds of millions of years ago, mitochondria evolved from certain types of bacteria that were engulfed by other bacterial forms. A mutually beneficial relationship developed between the host cells and the newly incorporated bacteria and this successful partnership was passed on to all animal cells, including our own. A similar merger occurred in the evolution of another cell structure called chloroplasts, which are big players in plants and other photosynthesizing lifeforms.

So, if you continually exchange matter with the outside world, if your body is completely renewed every few years, if you are walking colony of trillions of lifeforms, and if your human cells still incorporate bacterial ancestry, exactly what is this self that you view as separate? You are not an isolated being. You’re an ecosystem, a complex, self-regenerating amalgam of lifeforms that interact communally to form a larger whole. Metaphorically, to think of your body as a machine, as current bias would hold, is inaccurate at best and destructive at worst. You’re far more akin to a whirlpool, a brief, ever-shifting concentration of energy in a vast river that’s been flowing for billions of years.

We’ve only begun to fathom the implications of this profound notion, but it’s one that deserves to be disseminated and discussed widely. I think that the dissolution of our separate selves can help us see the world in new, more accurate, and even sustainable ways. What do you think?