Where Do Bodies End?

I recall once long ago reading a piece, of the scientific sort, in which the author pointed out that discovering where our bodies end (or start) is rather difficult—provided we have sufficiently accurate measuring instruments. Some of the air that surrounds us will soon be incorporated as flesh and blood as we breathe it in. Some of what we breathe in is dust. Does it become our body? Or should it be segregated, at least statistically, as Not Me?

When tonight I take out our garbage, and it sits on the curb awaiting pickup, it remains, manner of speaking, our property; indeed I may not put it out until after 6:30 or the city could give me a citation. But we’ve already let go of it. When I breathe out the spent breath, stripped of oxygen, it remains around me, for a while anyway, except in a strong wind outdoors.

We’re surrounded by two auras minimally—the more or less solid kind of smells (read chemicals) and dried skin and hair being shed; the other is heat radiating from us, and if the right instrument is used, the heat is quite high as it flows from ears and eyes and other openings.

Who can draw the precise border between skin and clothing when these two phenomena interact so closely? And then there are those empires of one-celled creatures that cohabit this structure, my body, with me. When some tribes of nations of that empire are absent, I cannot digest my food. Some bacteria, airborne away from my body, enter other people’s by contact or by indrawn breath. (This is getting gross, and I apologize, but it is so.) In places frequented by people, bodies, in a sense, certainly at their aural extensions, mingle. And we do shake hands and sometimes hug. Attend a crowded concert. Visit a state fair where the bodies of farm animals share the space. Perceived by means of exaggerated science fiction senses, we are walking (sipping extra large cups of sugared soda, yes even in New York City still), we are as it were swimming through an ocean of shed skin, hair, bacteria, chemicals, heat, aerated sweat moisture, and discarded breath.

All this is objectively true. Very expensive experiments would prove it so. And as immediately outside us—so also deep within. We feature what is known as a microbiome made up of many nations and tribes of archaea, bacteria, and fungi (see illustration of just the cohabitants of our skin from Wikipedia link). Which illustrates that, even in quite banal and ordinary circumstances, our take on reality is merely probabilistic. What we are, as bodies, is virtually unmappable except in continental detail. Yet when it comes to us, to the me writing this, and never mind the bodily tooling that is keying these immortal words, that me is not locatable at all, not even with electron microscopes.