Take a one-year-old baby and show her a few different shaped objects, one after the other. As you present the baby with each object, either say to her: “look, a wug!’’ or “look, a fep!”. Only by introducing two made-up words, in this case “wug” and “fep”, is the baby likely to perform an extraordinary feat: creating, all by her own, some similarities between the wugs and some other similarities between the feps. It may be their colour, their size, the sound they make or any other feature that the baby is able to perceive. In this way, you’ve helped the baby create something that does not really exist, a brotherhood of wugs, a brotherhood of feps and a frontier between wugs and feps. Such is the power of words.

Ours is a world of words, of  wugs  and  feps,  of brotherhoods and frontiers, most of which, if not all, only exist in our imagination. Nature doesn’t have clear borders, if it has borders at all. Bring in the microscope and you’ll find worlds within worlds within worlds in every border you set your eyes on. In fact, what quantum mechanics, the physics of the very small, is telling us is that if we could set that imaginary microscope to the maximum enlargement, we would no longer see things, but only interactions. Down at the very bottom there is not even substance; there’re only relations.

In nature there are no  wugs  and  feps;  everything is multiform and relational. To make this case, let’s inspect a rock in the forest. That rock is the home of mosses and small bugs that live on its surface. It also keeps the soil humid and gives protection to other bugs beneath its body. It’s an obstacle for the roots of the nearby tree, it’s a hiding place for the snake, and a lookout for the rabbit. After a rainy day it contains tiny ponds where travelling insects stop for a drink, and it’s a warm surface to rest on when the sun hits its skin. You may sharpen sticks on its rough skin, use it to build the walls of your new country house or use it to help you channel the rainwater. The rock isn’t one thing or the other, it’s all of them and uncountably more; altogether, all at once.

When you go to any modern house however, every single object is made into a  wug  or a  fep.  You may use a chair as a ladder and possibly for two or three more things, but chairs are meant for sitting. The same goes for all the objects in our house and most objects in cities. We surround ourselves with objects moulded to facilitate our habits, tailored specifically for our size and shape. So much so that if we all suddenly tripled in size, entire cities would become completely useless, purposeless and obsolete. The frontiers and brotherhoods would reveal themselves as absurd.

However, as much as we may try, we can never separate anything from nature. How can we ever separate anything where no boundaries exist? In nature, a chair keeps holding all its multitudes just the same way as that rock in the forest. The frontiers are in our imagination not in the chair. Because we build frontiers we find ourselves continuously acting as border patrols. This is what we do when we are cleaning, organising or enforcing proper use of space and objects. 

The most powerful weapon for safeguarding our borders are words. With our hands we can mould the physical world to our shape and size; we give form to objects. Words give them a name. They draw the lines that separate one thing from another in our mind. The names of colours are a classic example of this. If you’re looking for a green shirt in a shop and the assistant hands you a light green shirt you may or may not like the shirt, but you won’t complain that it’s not green. But if you ask for a red shirt and the assistant hands you a light red shirt you will most likely say, “Hey! I asked for red, not pink!”. We’ve built a very tall wall between red and pink thanks to “red” and “pink”; a wall that only mildly exists between light green and green. But if you volunteer to go around the world preaching: “Look, this is olive!”, “Look, this is mint!” and “Look, this is lime!” and make a fuss about it you may start building walls between greens which didn’t really exist before outside of printers. 

The borders we build in our imagination give structure to our surroundings. It’s because we can create borders that we’re able to build sophisticated objects. Without  wugs  and  feps  there would be no bicycles, no cars and no man on the moon. To build a bicycle, for instance, we must create  wheels, pedals, cables, cogs, forks, brakes, handlebars  and a long etcetera. These pieces are not out there to be collected from the ground. Giving each of these parts a name grants them full independent existence. You may be able to cook a couple of fried eggs without using words, but try, without using words, to cook a coconut cream and fruit-topped vanilla cake for diabetics. Even if we already recognise the pieces words are helpful. There is an experiment where participants had to jointly build lego structures. Their performance substantially increased when they gave names to the pieces they were using. Creating clear frontiers and brotherhoods helps us build more complex structures. 

When we want to name something new we rarely bring about made-up words like  wug  or  fep.  We usually reuse names of familiar things. In nature, when something proves useful it is reused. Sea-life works as a good example of this. We’re obviously more familiar with what’s outside the sea than we are with what’s hidden in its depths. So there is a very long list of sea creatures with names inspired by our terrestrial life: seahorse, rockfish, swordfish, sailfish, wolffish, mosquitofish, moonfish, scorpionfish, guitarfish, trumpetfish, and of course, the clownfish and surgeonfish, to name just a few. “Things are named by their qualities” says the archaeologist A. H. Sayce, “but their qualities have first been observed elsewhere.” Another example is our extensive use of names taken from our body parts: the legs of the chair, the mouth of the river, the face of the moon, the head of a nail, the skin of an interface or the foot of the hill. An example that I love is from the Western Apache language, where all the parts of a car are named after our body parts. Thus, the “nose” is the hood; the “eyes” are the  head lights; the “hands and arms” and “feet” are the front and back wheels respectively, they use “liver” for the battery, “intestines” for the radiator hoses and “stomach” for the petrol tank, and the list goes on.

What these examples reveal is that despite all the boundaries we build, nature keeps leaking through the walls. Despite the obvious differences between the moon and a fish, we can still see something moonish in that fish, enough to call it a moonfish. And similarly, we can see something mouth-like in the mouth of the river, and something skin-like in a graphical user interface. As the philosopher John Dewey said “any sensuous quality tends, because of its organic connections, to spread and fuse.” The sensuous qualities of the moon has spread to the sea to fuse with a rare big white fish, the moonfish. 

These sensuous qualities through which we experience the world around us, cross all imaginable boundaries. How else could we have loud colours, bright sounds, stinging smells, silky tastes and a sweet touch? According to neuroscience, the spreading and fusing of these sensuous qualities may be caused by leaks in the electrical flow that runs through our brain. Neurons that are activated by the sensuous qualities of one of the senses, say vision, may spread their electrical impulses to nearby neurons involved in processing another sense, for example touch or hearing. Thus, a phantom, or an echo, of what we experience in one sense may actually be experienced by another sense. At least, enough for us to experience a singer with a warm velvet voice and a subtle touch of brightness that makes sweet music. 

The neuroscientist V.S. Ramachandran speculates that these leaks in our brain, that allow us to hear with our eyes and listen with our hands, are key for our capacity for abstraction. Once we detach roughness from touch, darkness from vision, bitterness from taste, we have a fertile soil for metaphors. And once we have metaphors we are able not only to grasp objects with our hands, but are able to grasp ideas with our words. The roughness of the surface felt initially with our touch may be exported to experience the roughness of a day, of a relationship or of an idea. The clarity experienced looking at an extensive landscape under a bright blue sky may be exported to experience the clarity of a theory, a business offer or a legal contract. The sensuous qualities experienced in our physical world make use of the leaks in our brains to cross the borders between the tangible and the intangible, the concrete and the abstract, the visible and the invisible. This trespassing is the essence of metaphor.

The word metaphor is itself a metaphor. In ancient Greek, it literally means “to carry over”, “to transfer”. Even in modern Greek the word metaphor, written μεταφορά, means “transport”. If you want to visualise the meaning of metaphor make an image search of the word “μεταφορά”. Metaphors takes the qualities of one thing and  carry them over  to something else. Or in the words of the poet Kenneth Burke, “it brings out the thisness of a that, or the thatness of a this”. Far from being merely a figure of speech for a few poets, metaphors have shaped, and will continue shaping, the very way we think. 

“Every modern language,” says the philosopher Owen Barfield, “ with its thousands of abstract terms and its nuances of meaning and association, is apparently nothing, from beginning to end, but an unconscionable tissue of dead or petrified metaphors”. We don’t feel particularly poetic when we say that: a concept is  brilliant,  that a legal system is  flexible,  or that a theory is  hard to swallow.  However, if taken literally, and not metaphorically, those sentences have a very peculiar meaning. But we can dig much deeper than that, because metaphors don’t just embellish the surface of language, they are part of its very foundation. The word  concept, for example, comes from the Latin  concipere,  meaning “take in and hold” or else, “to become pregnant”. The word  system  derives from the ancient Greek  synistanai  which means to “place together or organise”. The word  theory,  derives from the ancient Greek  theorein  which means “to consider or speculate”. If we trace this word further, we find that  theorein  derives from the word  theoros  which means “spectator”. Whenever we’re able to trace back the origins of our words, we eventually stumble upon our body interacting with its environment, we encounter the physicality of meaning. “A man cannot utter a dozen words” continues Barfield, “without wielding the creations of a hundred named and nameless poets.”

Such is the power of poetry, from one world it can create another. Using all of our senses as raw material, poetry can give shape to the ineffable. In fact, the word poetry derives from the old Greek word  poïesis,  which means “to make”. That is, poetry was once a verb, an action that could convert thought into matter. I once heard that the most revolutionary technologies are those that allow us to see what was before invisible. The microscope and telescope being the classic examples. Poetry, in that sense, is our innate, inexhaustible revolutionary technology; it renders tangible the intangible once and again. “The poet” says the philosopher Gaston Bachelard “speaks on the threshold of being”. The poet can bring into existence what no one has ever imagined before. Quoting Bachelard again, “the poetic act has no past”.

Poetry isn’t about the poem nor the words, it’s about transforming the way we see the world. In the past, poetry and science used to be one and the same. The main tool they used to harness the intangible remains the same: the metaphor. “When a physicist says an electron is like a particle he is making a metaphorical comparison like the poet who says ‘love is like a rose’” writes the physicist Douglas Giancoli. Both electrons and love are intangible; they’re abstract. Electrons are not particles and love isn’t a rose. But through metaphors we enrich the meaning of both: they become slightly more concrete so that we can grasp them. One of the greatest poets of modern times may be our dear old Albert Einstein. He transformed time into space, and space-time into a curved valley. He said that gravity is like acceleration, converting our planet into a lift that always moves upwards. And he wrote that matter is like energy. What can be more poetic than that?

Words play a fundamental role in the imaginary edifice of borders and brotherhoods that we have created. However, on their own, words are nothing more than short funny-sounding exhalations of air. What really sits at the heart of this imaginary fabrication is that we’re hard-wired to perceive the intentions of others. When you say to a baby “Look a wug!” what’s most salient for her is not the object that you’re pointing at, but the very fact that you’re pointing at something; that you want something out of this situation. That is, that you have an intention. It’s as if she sees you standing there with a bow and an arrow, and as you stretch the bow she has to figure out what you’re aiming at and what your target is. Only by tuning into your intentions can the baby, or any other human being, make sense of the target you’re aiming at. And if we do tune in we may even make sense of invisible targets. 

This colossal fiction we’re immersed in, with all its poetry and all its science, can only exist because our brains are built to connect with one another. When two humans initiate a communication they instinctively try to tune in with each other to establish common ground. This appears to be a unique feature of our kind. When other animals, like chimpanzees or bonobos, gesture to one another they simply want something done. We gesture to establish a connection with the other person, to get on the same wavelength. Once we establish this connection, once our intentions fuse and the frontiers that separate my brain from your brain blur, only then does it make sense to say ‘love is like a rose’ or ‘an electron is like a particle’. This connection isn’t completely metaphorical. Neuroscience argues that simply by thinking about someone we know, we become more like that person, and this change is measurable in our brain.

The borders we’ve created in building the social reality we live in may only exist because nature doesn’t have natural borders. Even further than that, the borders that might exist, those that separate one sense from another, the concrete from the abstract and my brain from yours, are trespassed once and again with complete impunity. The boundaries of our imagination are only in our imagination, secured by a network of interconnected borderless brains. We agree to call this fiction reality. For us, building new brotherhoods and frontiers comes easily. We have to steal the  thatness  of this or the  thisness  of that to create something new, and nature is anything but short of thatnesses and thisnesses. Building walls is easy, taking them down is the hard part. It requires that we accept that much of what we call reality is no more than a story we tell ourselves.