“It is very last inch of us…but withnin that inch we are free.”
-Alan Moore, “V for Vendetta”
Our digestive system is home to a huge number of microscopic organisms. Most of these are bacteria, but viruses, archaea and fungi are also present. Although previous estimates suggested that the cells of such organisms present in our bodies outnumber our own “human” cells ten to one, more recent estimates give a lower figure, indicating that number of those cells is about the same as that of our own cells. Even though this ratio isn’t as impressive as a 10-fold one, it’s still astonishing; being human means having a body that’s at least half bacteria and other creepy organisms we don’t know much about.
By the way, the scientific term for our bugs is “microbiota” (the microscopic life occupying a specific region). In this article we are talking specifically about the gut microbiota (the microscopic life occupying our gut).
At least these guests in our guts pay the rent, in their own Cunningham way: they help our immune system mature, regulate the movement of our gut, help absorb nutrients and distribute fats, and probably have other benefits as well. Due to its diversity, it has been estimated that the gut microbiota has at least 150 times as many genes as we do; this basically means that our bugs are capable of performing a lot more biological functions that we would be able to. This is probably the reason humans find themselves in this relationship anyway: bugs do things that are helpful and that we can’t perform (at least not as efficiently) on our own.
Bonus fun fact: a study published in 2015 showed that gut bugs are like a fingerprint: their unique composition can be used to identify you. So don’t leave your poop at the scene of the crime!
Having found that at least half of the cells in your body belong to bugs, you may try to find solace in the idea that what makes us truly human is our brain. But this consolation is likely to provide scant comfort, because for better or for worse, the bugs can probably control some functions of our brains as well.
Scientists have established that our brain and our bugs are able to communicate; our brain influences our microbiota and our microbiota influences our brain. The mechanisms and effects of these interactions are still unknown, though. However, studies in animal models like mice and rats have thrown a ray of light on some interesting phenomena. Diet, drugs (like antibiotics) and disease can alter the composition of the gut microbiota, and this correlates with the release of substances called cytokines, which can affect brain function. Stress can alter the composition of the gut microbiota of our cousin mammals. Gut bugs can produce several substances used by our nervous system for communication; this potentially allows them to directly influence brain function. Again, most of these studies have been performed in animals, and the results of research concerning the mechanisms and effects of the bugs’ activities in humans have not completely emerged yet. However, some thrilling pieces of data have been uncovered; for instance, humans with neurological disorders like autism and schizophrenia tend to have digestive system problems as well.
Much as we would like to think that we have agency over our thoughts, it’s likely that the bacteria and other organisms in our guts affect us in more fundamental ways than we’ve ever dreamed of. The only silver lining to our concerns about privacy online is our belief that we are still free in our thoughts. And yet, we seem to have lost that “last inch” a long time ago when we got into a relationship with bugs that altered us in ways we might not have anticipated.
Aside from our internal bugs, think also of the external factors that affect our thought processes and choices: how music invites us to feel emotions we might not feel normally, how pervasive fast food chains encourage us to eat unhealthily, how social pressure subtly nudges us to dress a certain way, how movies and television inspire us to adopt certain lifestyles, and how advertising makes all this glitter look like gold. The internet magnifies these effects: it connects human society in a way that wasn’t possible before, and increasingly paints people in the same shade. All of us have some awareness of this inexorable influence, and the deep roots it has put down.
So our human bodies are not really human, our human thoughts are not human either, and on top of that, our society insidiously places myriad other thoughts inside our heads.
Considering all this, to what degree can we possibly be individuals? Do we have any thoughts that are purely our own?
Do our experiences make us individuals?
We had a childhood, we grew up, we fell in love, and we lost loved ones to death. The time and the order in which we experience life is different.But all the innumerable human beings who have passed through this world have shared the human experience. Ultimately all human experience, to the degree that it matters, is the same.
So, if it’s not our experiences either, perhaps it’s our creativity that makes us individuals?
Even when we create new things, are we just putting together old ideas in new combinations, “standing on the shoulders of giants” to look further?
Is that combination of old thoughts still a new thought? Perhaps it is, and maybe art is a new way of looking at the same themes. If, in this sense, art is an expression of our humanity, and our individuality, then science is the grander experience: the use of our individual thoughts to create something that was not before, the search for new ideas using old tools, or the creation of new tools to look for unknown ideas. Science is new thought. Perhaps this is individuality. But even science, to some degree, does not hold up under scrutiny. If Newton hadn’t existed, someone else would have eventually figured out the law of universal gravitation. Leibnitz and Newton discovered calculus around the same time. Art is all worn out, and science is independent of the individual.
We are not completely human. We are not individuals either. With these cheerful thoughts, I welcome you to the new semester!