A friend recently asked me the same question.
And I’ve been asked it before, too. Why would somebody be more interested in organisms that are invisible? I usually hear the same retort, that one would rather imagine life forms we can see as more interesting, as tangible. After all, our senses can readily detect them: fields of corn have a distinctive smell, I can hear a river dolphin breach the water’s surface, beetles are visible, a dog’s fur is coaxing to the touch, and the tang of blue cheese derives from its added Penicillin culture.
But Robert Hooke argued the opposite. His Micrographia is, by our historical record, the first account of using a microscope to examine the world beyond the limitations posed by our sense of sight. Maybe Hooke was foreshadowing the Darwinian struggle against anthropocentrism when, in the first pages of his book, he claimed that the human senses are by no means superior to that of other beasts. What we can see, Hooke argued, is fallible due to the limitations of the senses, particularly here, of sight and visual perception. He wrote,
As for the actions of our Senses, we cannot but observe them to be in many particulars much outdone by those of other Creatures, and when at best, to be far short of the perfection they seem capable of: And these infirmities of the Senses arise from a double case, either from the disproportion of the Objects to the Organ, whereby an infinite number of things can never enter into them, or else for error in the Perception, that many things, which come within their reach, are not received in a right manner.
Besides his ardor for the lengthy sentence, Hooke was adamant about the unreliable nature of human sight and memory. It was precisely because we can see the surface of a leaf that Hooke desired to use his microscope to probe the minute scale of its green veins. Although Hooke is famous for coining the term “cell” in the natural sciences, he didn’t see microorganisms. But his text does give something of a certain proximity to the world around him, a refusal to accept things as they seem on the surface.
It wasn’t until roughly twenty years later that somebody took this endeavor to the next scale. Anton van Leeuwenhoek was no scientist; he sold cloth for a living, and unlike Hooke, who lived in the scientific metropolis of London, Leeuwenhoek belonged to Delft, Holland. Inspired by the 1665 publication of Micrographia, Leeuwenhoek began to grind his own lenses and made a series of simple microscopes (looking back, however, his were hardly more than powerful magnifying glasses). Like Hooke, Leeuwenhoek began to investigate the world around him, albeit from a different angle. Some of the first objects he viewed with these lenses included the plaque from between his teeth, pond water, and his excrement. And what he saw in each of these samples, for arguably the first time in our history, were moving, darting, creeping forms.
On December 25th, 1702, Leeuwenhoek wrote the following on what he observed in the drop of pond water.
In structure these little animals were fashioned like a bell, and at the round opening they made such a stir, that the particles in the water thereabout were set in motion thereby. And though I must have seen quite twenty of these little animals on their long tails alongside one another very gently moving, with outstretched bodies and straightened-out tails; yet in an instant, as it were, they pulled their bodies and their tails together, and no sooner had they contracted their bodies and tails, than they began to stick their tails out again very leisurely, and stayed thus some time continuing their gentle motion: which sight I found mightily diverting.
The animal-like organisms he was here describing are the ciliated protozoa, Vorticella. And Leeuwenhoek made the same analogy to animal life when he described the bacteria he discovered between human teeth, below.
I then most always saw, with great wonder, that in the said matter there were many very little living animalcules, very prettily a-moving. The biggest sort, had a very strong and swift motion, and shot through the water (or spittle) like a pike does through the water. The second sort, oft-times spun round like a top, and these were far more in number […] The biggest sort, bent their body into curves in going forwards. Moreover, the other animalcules were in such enormous numbers, that all the water, seemed to be alive.
From the Latin animal and culum, Leeuwenhoek’s term “animalcules” literally means, “little animals.” In relating bacteria and protozoa to animals, to fish like pikes, this cloth salesman demonstrated a certain intimacy with these creatures. He was the first to see them, their motions, and their activities, and his description of his observations, “with great wonder,” is both revealing and unsurprising. From Leeuwenhoek’s time onward, from Victorian naturalists to modern molecular biologists, using book titles such as The Psychic Life of Microorganisms to Wetware: A computer in every living cell, the curious have explored what the world of animalcules might be like, from the microbial point of view.
At stake in Leeuwenhoek’s discoveries, and his unique position of observation, was in making something invisible visible and knowable. From his simple exploration of a single drop of Delft’s pond water, microbiology was birthed, leading to classifications of pathogenic organisms, advances into the germ theory of disease, and modern antibiotics and vaccines. In The Birth of the Clinic, Michel Foucault gives an insight on this style of observation and a connection between this 17th century natural history and the rise of Western biomedicine. On the new way in which physicians began to view disease and the human body, he writes,
Modern medicine has fixed its own date of birth as being in the last years of the eighteenth century […] The relationship between the visible and invisible, which is necessary to all concrete knowledge, changed its structure, revealing through gaze and language what had previously been below and beyond their domain. A new alliance was formed between words and things, enabling one to see and to say […] The clinic demands as much of the gaze as natural history. As much, and to a certain extent, the same thing: to see, to isolate features, to recognize those that are identical and those that are different, to regroup them, to classify them by species or family.
The relationship and alliance Foucault speaks of, and the intimacy both imply, is my answer. In The Theory of Religion, Georges Bataille argues that the entire function of religion, throughout human history, has been to reclaim a lost form of intimacy with non-human life. Bataille outlines the routine state of affairs in nature wherein “every animal is in the world like water in water.” By this, he means that between predator and prey, host and parasite, rabbit and squirrel, there is no tie of subordination, no master-slave relation. This association, Bataille argues, can only exist through consciousness, when one views itself as a subject. In doing so, Bataille states, the stable relationship of animal-to-animal, water to water, transformed to one of subject-and-object. Life forms—the plants, the animals, the protozoa, the fungi—became reduced by human consciousness to the status of thinghood and the arbitrary value placed on them by human use. Bataille’s thesis rests on this concept, and his following theory throughout the text is that the earliest religions, recognizing this lost intimacy with nature, performed sacrifice to, in essence, “free” the animal from its status as tool, as object, as something solely for human consumption or use. In killing it and wasting its flesh, the intimacy of this primordial relationship, which became deified, could be released.
I do not wish to engage in an association between science and religion; that has not been the point of this train. And it’s time to return to the ground. Why microbial life, why does it fascinate me? Reclaiming an intimacy with organisms I cannot see, making something visible out of what lies beyond our perception, both are achieved through an interest in what the 17th century called the invisible world. I agree with Hooke; our senses are faulty. The visible world is fascinating, it is tangible, I can touch it and taste it. But it is for those reasons too that this other realm better engages my interest. To see the same sights Leeuwenhoek first saw centuries ago, to feel a rush of language abandon a description of alien bodies and mechanisms, these are my answers. To see something large in something so small, is akin to what Gaston Bachelard meant when he wrote, “The minuscule, a narrow gate, opens up an entire world.” To see something completely new to one’s eye, at each gaze into the microbial, is the closest thing to magic.