I lean back in my chair after a good meal. I place my utensils at the four o’clock position on the plate. My plate, which was perfectly fine just a moment ago, is now dirty. The scraps of food still on it are now leftovers or even worse: “refuse”, “garbage”. What happened? Every single item in front of me is exactly as it was a few seconds ago. There is no change in the chemical composition of the stuff itself. What then is the difference between dirt and non-dirt? How did the change come about?
When we put the question this way we can expect the obvious answer: “There was no change. It was all just a matter of cultural preferences and human subjective feeling.” Unfortunately, that is not a reply I can give when my friend asks me to help him wash up. From every practical point of view, the fact that things around us may be soiled is inescapable physical reality. It is in fact difficult to think of a practical activity where concerns about dirt and soiling have no place at all.
It would of course be absurd even to start looking for a chemical formula for dirt. As chemist Justus von Liebig famously said, “Für die Chemie gibt es keinen Dreck” – for chemistry, no filth exists. Dirt, as it were, dissolves in the chemical investigation. Collect some of the red wine sauce from my plate and put it into a test tube. Whatever stuff is now there for analysis is simply some chemical substance or other. For obvious reasons, chemists must always make sure their equipment is absolutely clean, but the word “dirt” itself does not belong to the theoretical vocabulary of natural science.
Philosophy, at least of the English-speaking mainstream, has for many years now been committed to naturalism, the general view that the world, as it really is, should ultimately be described in terms that belong to the explanatory vocabulary of theoretical natural science. To put it bluntly: Dirt does not exist in physics or chemistry books. Hence it does not really exist at all. Or that is the idea, splendidly expressed by Liebig.
What about this suggestion then: “Dirt does not exist, but what do exist are health hazards.” For good evolutionary reasons, we tend to react with disgust to possible carriers of contagion like spoiled food and faecal matter. At least some part of our reaction to dirt has a medical basis and it can be made palatable to science. The problems with this view, however, are numerous, at least if it is meant to be a general explanation of why we prefer the clean to the dirty.
It is plausible that our aversion to dirt has some of its roots in the early evolution of hominids. But that does not really explain our ideas of dirty and clean at present. Perhaps it all started with instinctive ideas of health hazards, but what was perhaps true a million years ago is definitely not so today.
Our everyday reactions to dirt mostly have little to do with ideas of health risks. Sociologist Norbert Elias writes,
“Someone who eats noisily or with his hands nowadays arouses feelings of extreme distaste without there being the slightest fear for his health. But neither the thought of someone reading by bad light nor the idea of poison gas, for example, arouses remotely similar feelings of distaste or shame, although the harmful consequences for health are obvious.”
We don’t like stains of food on furniture, but we hardly blink at some things that are much worse. We shake hands with strangers unless we are medical doctors on duty. We exchange kisses, we use public transportation and we have cats and dogs indoors.
For the most part, our preference for a clean environment has more to do with our feeling for the aesthetics. It sometimes prompts us to adopt aesthetic solutions that go diametrically against aseptic hygiene. We frequently prefer dark or patterned fabrics and wallpapers precisely because they make soiling less visible on clothes and interior decoration. This is of course also why unmixed white would be the superior colour from a purely hygienic point of view. Seeing that the ideas of hygiene and cleanliness pull in two different, sometimes entirely opposite directions, they must mean different things.
If dirt does not exist for science, should we then just say it is a matter of cultural convention? Perhaps it is symbolic, a social construct, perhaps? That is probably the preferred view in research today. Anthropologist Mary Douglas, the Grande Dame of research on pollution, defined dirt simply as “matter out of place”. A dirty substance in itself is not the problem, but the fact that it interferes with our ideas of a well-ordered world somehow is problematic.
Douglas, I believe, is right in one way and wrong in another.
Douglas is right in saying that dirt is something we feel should not be there. Nature in itself is always pure, if untouched by a human hand and unseen by a human (or conscious, animate) gaze. Dirt is a shortcoming, and it exists only in the kind of environment where we feel that we should put matters aright. Or at least someone should.
Douglas is, however, wrong to conflate dirt with disorder, which is not necessarily the same thing at all. To tidy up a room is not necessarily to clean it, and I can clean things without changing the way they are (dis-) ordered. There are places where dirt is indisputably in the right place. A sign at Heathrow Airport said some years ago,
“There’s a home for everything –
Please use the bins provided.”
Leftovers in the dustbin certainly count as unwanted matter. But to say dirt is out of place in this sense (i.e., unwanted) does not seem to imply anything more than just that dirt is dirty.
Douglas is also misleading in another and, for philosophy, more hazardous way. She wants to say: There is nothing either dirty or clean, but thinking makes it so. This seems to be based on the simplified argument that if dirt is not a scientific category then only one alternative is left. Dirt must be subjective, it must be symbolic. In theoretical debate, taking a cue from Douglas, it is typically assumed that descriptions like “dirty” and “soiled” have more to do with social categories like “forbidden” than with material qualities like “wear and tear”, “wet”, “rusty” or “damaged”.
Instead of addressing the materiality of dirt, researchers like to dwell on the numerous ways dirt can symbolically stand for something else like sin or minority status. Nothing wrong with that analysis, perhaps, but it leaves out what is the most obvious thing about our cleaning efforts. We clean things primarily not because we want to make a symbolic statement but for the same reason we repair things when they are damaged. Dirt and damage are indisputably there and something must be done about them.
What’s the use of philosophy if it just throws in the towel and tells us to go to the scientist instead? Dirt does not have to be non-existent or merely symbolic just because it is not mentioned in a chemistry book. There are, after all, other meaningful ways than science to engage with the material environment. The task of philosophy should not be to explain away human experience, but to make sense of it.
I believe the question, “What is dirt?” is closely related to another question: What is a thing, what is an ordinary object? And we can understand that, not from physics and chemistry but from attending to the lives of human beings with ordinary objects. That is a kind of symbiosis. The evolution of the species has, at the same time, involved the development of a humanly shaped world of artefacts.
Oswald Spengler, author of The Decline of the West, remarked in 1931 that “the earliest traces of man and his tools are the same age”. It is impossible to imagine the fully developed human hand as active even for a short while without the existence of tools. “Just like the tool was shaped in conformity with the hand, conversely the hand arose from the shape of the tool”. My suggestion is that this symbiosis of man and thing also gives us the concept of dirt as we know it.
Our symbiosis with ordinary objects implies that we do not just view the physical world from afar, neutrally as theoretical science would have it. Our ability to recognise any ordinary object at all is tied up with values. We cannot help thinking that it is better for the objects of our environment to be one way rather than another. If you know what a glass is you will also know you shouldn’t drop it on the floor. You will also know it must be cleaned after use.
Philosopher Thomas Leddy speaks of “dirty”, “clean”, “messy” and “tidy” as “everyday surface aesthetic qualities”. By calling “dirt” a surface quality he does not just mean that dirt often collects on the surfaces of objects. Instead, he connects dirt to the idea that ordinary objects have essences. Here he goes back to the mediaeval (originally Aristotelian) distinction between “substance” and “accident”. “Accident” does not, in this context, mean “road accident” (as in a police report) and “substance” does not mean “drugs” (as in a police report). Substance is the object or thing as it really, essentially is. Accidents are additional qualities that lie, metaphorically, on the surface of the object without changing its underlying identity.
A plate on the dining table may be both cracked and dirty, but the cracks and dirt count as accidents because they do not change its basic identity. At the same time, we tend to look at these shortcomings against the background of the ideal case. We recognise dirt and damage because we can envisage the original plate in its undisturbed state. To be cleaned is for the object to return to something like its original condition, but now with the difference that it is the result of human effort.
As soon as we have ideas of an object or a thing we also have ideas of what really belongs to it and what is an additional, unwanted quality. Our lives are a constant fight against damage and dirt, an ongoing effort to maintain the things we have created in their proper condition. This is a necessary feature of all material culture and hence a defining condition of the human form of life. As Genesis states, we were put to the Garden of Eden “to dress and to keep” it. We have an idea of being in charge of our extended home, which is the world or the Creation.
Dirt is a deviation from the ideal state of the object, the state of the object as it really is or should be. This also means that soiling is relative. It is not relative to human opinion or human sensibility, but relative to the kind of object we think we are facing.
An interesting case has been related by Anna Magdalena Midtgaard, working at the Rare Books section of Copenhagen Royal Library. Major libraries today have custom made vacuum cleaners for books, and there are also techniques for washing and ironing book pages. Some librarians find it important as far as possible to remove stains and dust from old volumes, thinking of the new volume as the ideal. Others would take a more conservational approach. Grains of pollen and sand may be seen as belonging to the volume’s history. They sometimes contain useful information about its place of origin and the hands through which it has reached its present location.
The variety of existing attitudes among librarians not only reflects differences of taste, but also ideas about the identity of the item itself. A stain on a book may either be seen as a blemish or as patina: either as something external to the volume or as a natural feature of it. Technically speaking, patina is impossible to distinguish from wear and dirt, but the description of it as “patina” implies that it would be barbaric to remove it. The old manuscript volume must give us the message, “I am 500 years old”; but it must not necessarily cry out, “I was new 500 years ago”.
“Are your hands clean?” – Just like that, out of the blue, it is impossible to answer that question. The answer must depend on what you expect me to do with my hands. My hands may be perfectly clean for us to shake hands, but if I want to touch the manuscript I must wear protective gloves. That is, quite simply, what it means to handle an object of that kind with care. On the other hand, if I wear gloves when we shake hands you may see it as an insult. It is as if I fear contagion. What is the right thing to do will depend on the situation. That is not because dirt is subjective but precisely because it is not.