Can something be False but Not Fake? Taking a Look at the Images from the James Webb Space Telescope, Geiger Counters, Your Brain, and the Amazing Realm of PerceptionRead Now
Many of us are were awed by the release of the first pictures taken with the James Webb Space Telescope (JWST). The telescope’s crystal-clear images identified previously unseen galaxies, which formed just a few hundred million years after the Big Bang, giving a us a closer glimpse of the early universe. It also revealed many new instances of gravitational lensing, a phenomenon predicted by Einstein, where a strong gravitational field bends light. And it identified many stars in the process of formation enveloped in clouds of dust and gas exposed to titanic forces unleashed by galaxy collisions or the explosion of older stars.
However, not everyone was thrilled. A group of skeptics started arguing that the photos were fake, and the fact that the first photo of the JWST was unveiled by President Biden in a ceremony at the White House provided the politization element. Someone also pointed out that the name of the galaxy cluster featured in the first image, SMACS 0723 (which stands for Southern MAssive Cluster Survey), reads “SCAM” when spelled backwards. Conspiracy theories arose claiming that the fake images are a cover up and the telescope is really a spy satellite or a weapon of some sort. It also didn’t help that a scientist as a joke posted an image of a slice of a sausage and claimed that it was an image of a nearby star taken by the JWST. Additional confusion was caused by the information that the colors in the images were not the original colors (they were false colors!), and that the images underwent a lot of computer processing (manipulation, eh? nudge, nudge; wink, wink) before being released to the public.
So there you have it. A presidential photo op, hidden word messages, false colors, computer generated images, fake science, and conspiracy theories. It’s déjà vu all over again! Shades of QAnon, the 2020 election lie, the 911 conspiracy, and the moon landing hoax.
All this nonsense is of course, fiction. However, as it has been stated many times by many people, truth is stranger than fiction.
There is a process called “transduction” where a signal of one type gets converted to a signal of another type. A classic example of this is a Geiger counter, where the signals produced by radioactivity (ionizing radiation) are converted (transduced) into sound by the sensors and electronics of the device. Radioactivity obviously does not make a sound. The sound is a false representation of the radioactivity, but this does not make the Geiger counter readings fake. This is because the sounds produced by the Geiger counter are correlated to the intensity and timing of the radioactive emissions. Thus, with the Geiger counter we can detect a phenomenon (radioactivity) that otherwise we cannot perceive with our senses.
The same thing happens with the images from the JWST. The images we have seen were taken with the telescope’s infrared cameras. But the problem is that much in the same way that we can’t perceive radioactivity, we also can’t see light in the infrared range. If we were to look at an unprocessed photo generated from the data from the telescope, we would just see faint darks and greys. The infrared photos have been converted (transduced) to the visible range much in the same way that radioactivity is converted into sound by a Geiger counter. Colors have been assigned to these images in order for us to see them. So yes, the images we see are in false colors and have been processed by computers, but they are correlated to the realities that the JWST is imaging. Thus they are not fake.
And in case anyone remains skeptical about this, just consider that YOU do this all the time.
Yes, you, or I should probably clarify, your brain, transduces signals all the time. In other words, your brain constantly changes one type of signal into another. Let me explain.
The light we see, the sound we hear, the odors we smell, the flavors we taste, and the things we touch are not sensed directly by our brains. They are sensed by receptors at the level of our eyes, ears, nose, tongue, and skin. These receptors then proceed to convert (transduce) these light, sound, odor, flavor, and touch signals into electrical signals. These electrical signals then travel to the brain through specialized structures in neurons called axons, and millions of these axons make up the cables that we call nerves.
So when we are exposed to light, sound, odors, flavors, and things we touch, what the brain perceives is shown in the figure below.
Those spikes in the image represent the electrical signals travelling down the axon of a neuron in time (the horizontal axis). This is the reality that the brain perceives. Not light, sound, odors, flavors, or the things we touch, but rather millions of these electrical signals arriving to it every second.
Now, do these signals make any sense to you? Of course not! The signals have to be transduced.
The brain does something similar to what the Geiger counter does or what scientists working with the JWST do. The brain processes the electrical signals coming from our eyes, ears nose, tongue, and skin and generates the sensations of sight, sound, smell, taste, and touch. These sensations are as false as the sound made by the Geiger counter or the color representations in the images of the JWST, but they are not fake in the sense that they are correlated to reality.
So, for example, we cannot see the wavelength of the light that impacts our eyes, but our brain associates the wavelength of the light with colors in such a way that we perceive light of short wavelength as purple and light of long wavelength as red. This association of false brain-generated sensations with the realities around us also takes place for the senses of sound, smell, taste, and touch.
So to wrap it up, what you see, hear, smell, taste, and touch is false, just like the sounds a Geiger counter makes or the color of the images of the JWST, but not fake, because these things are all correlated to reality.
Welcome to the amazing world of perception!
The image of the trains of electrical impulses belongs to the author and can only be used with permission. The image is the Cosmic Cliffs, a star-forming region of the Carina Nebula (NGC 3324), is by NASA and the Space Telescope Science Institute (STScI), and is in the public domain.
In Facebook I belong to a group that pays tribute to one of my all-time favorite comic strips, Calvin and Hobbes, written by Will Watterson. Watterson's strip about a hyperkinetic albeit imaginative kid named Calvin and his alter ego stuffed tiger, Hobbes, ran from 1985 to 1996 in the United States. Calvin, is the quintessential brat who often strains the nerves of his mostly tolerant parents, while Hobbes plays the straight man to Calvin’s antics. The comic strip often parodies modern life at the personal, family, and societal levels.
The most salient feature of the comic strip is Hobbes. When someone besides Calvin is around, Hobbes is shown as a stuffed toy tiger, but when Hobbes is alone with Calvin, he is portrayed as a walking talking tiger. This has been interpreted in several ways by fans of the strip, with some people claiming that the walking talking Hobbes is a figment of Calvin’s imagination while others claim that the tiger actually comes alive when he’s alone with Calvin.
One of the members of the Facebook group posted what Watterson once wrote about the ambiguity of Hobbes’ nature.
The so-called "gimmick" of my strip — the two versions of Hobbes — is sometimes misunderstood. I don't think of Hobbes as a doll that miraculously comes to life when Calvin's around. Neither do I think of Hobbes as the product of Calvin's imagination. Calvin sees Hobbes one way, and everyone else sees Hobbes another way. I show two versions of reality, and each makes complete sense to the participant who sees it. I think that's how life works. None of us sees the world exactly the same way, and I just draw that literally in the strip. Hobbes is more about the subjective nature of reality than about dolls coming to life.
I took exception to this, and I posted on the group’s page the following:
“This is not true. There is only one reality. We may perceive it in different ways, but those perceptions still have to have a high degree of correlation to reality for life to be possible. If I see the edge of a cliff and you don't, I will survive, and you will die. Seeing a walking talking tiger instead of a stuffed tiger is not just ‘another way’ to perceive reality, it is a fantasy. There are perceptions of reality which may make sense to some people, but they are false.”
A few people replied to my comment making several claims. Among these where that “everyone has their sense of reality’, that “there is no consensus regarding the interpretation of reality”, and that research into the quantum realm validates this notion; that “only those dogmatically adhering to their own perspective dare speak with any certainty when it comes to asserting that their interpretation of reality holds all due authority and finality in its validity”, and “what makes you an expert on reality? How do you know that for one a thing is not real that is for another?”.
I wanted to put together my replies to some of these comments in this post, because the implications go beyond a mere comic strip.
I understand that the perception of reality by different people can be different: for example, color blind people vs people with normal color vision. In fact, our perception of reality doesn’t even have to be “veridical”. However, as I stated in my comment, there has to be a big enough correlation between reality and our perception of it for life to be possible. All around us the world is full of patterns, regularities, and things happening one way and not another, that allow us to figure out how to go about living. Reality is not anarchical, and there are millions of consensuses regarding the nature of reality all around us. For example, the sidewalk under our feet WILL NOT turn into quicksand and swallow us, a tree WILL NOT uproot itself and chase us, a cloud WILL NOT turn into lead and fall on us, etc. We don't have to live in fear of these occurrences, because we have internalized how the world works. This ability is part of our evolutionary programing and has survival value.
Scientists go beyond this intuitive understanding of reality that we have all developed by performing tests to gain insight into more complex aspects of reality and they discard those views of reality that are incompatible with the evidence. With the exception of the quantum realm, so far all the evidence we have indicates that, at least at our level, we live in a deterministic world. Things are one way and not another. Some things are possible, and others aren’t.
I agree that some individuals see a reality that is very different from the one the rest of us see, but many of those people are unable to function in the real world and can even put their lives and those of others in danger. That is why they are treated with medication or locked up in psychiatric wards. Their view of reality IS NOT an “alternative view”, it is a FALSE view. I agree children often see reality in a way that is different from adults, but this is why they are treated like children and are under the care and supervision of adults. And it is our job as adults to assist in weaning them of their childhood fantasies, so they can take their place in the adult world.
Of course, when I post things like these, I come across as an arrogant, insufferable, “know better than thou” jerk divorced from the magic of childhood who is disrespectful of other people’s points of view. Let me just state two things.
1) I am a fan of fiction and fantasy. From Lord of the Rings and Harry Potter to comic strips such as Calvin and Hobbes, Bloom County, or The Far Side; and from the numerous incarnations of the Star Trek franchise (I’m a Trekkie) to many works of horror such as Frankenstein, Dracula, Aliens, Night of the Living dead, Nightmare on Elm Street, Psycho, The Texas chainsaw Massacre, or the Rocky Horror Picture show. I enjoy fiction and fantasy and find inspiration in them, so much so that I also write short stories. Fiction and fantasy have important roles in adulthood, but they ARE NOT reality, and as adults we must recognize this.
2) Reality is not a democracy, and alternative views of reality, especially those unsupported by evidence are not always valid or worthy of respect. Are the QAnon folks right in their claims of the existence of a worldwide cabal of satanic, cannibalistic, pedophiles? Was the 2020 presidential election a fraud? Was 911 an inside job? Is COVID-19 no worse than the flu? Will the COVID-19 vaccine modify your DNA and implant a microchip that will allow the government to track you? Was the moon landing a hoax and is the Earth flat? Was the Earth and all life on it created 10,000 years ago? Is the government spraying you with chemicals? These are not “alternative” views of reality, these are FALSE views of reality and should be treated as such.
So, to wrap it up, yes, by all means enjoy and be inspired by Calvin and Hobbes (or other works of fiction and fantasy), but all the while understanding that Hobbes IS NOT a walking talking tiger but just a figment of Calvin’s imagination.
Calvin and Hobbes image by Bill Watterson is a Wallpaper from flickr by Brad Arnold and is used here under an Attribution-NoDerivs 2.0 Generic (CC BY-ND 2.0) license.
“Seek and you shall find.”
Many people are familiar with this saying. It is one of those phrases that have permeated our culture. But where does it come from? This phrase comes from the Bible. It is part of the teachings of Jesus contained in the so-called “Sermon of the Mount” and detailed in the Gospel of Mathew. The specific reference is Matthew 7 (King James Version of the Bible):
“Ask, and it shall be given you; seek, and ye shall find; knock, and it shall be opened unto you.”
This statement in religious circles is normally associated with a search for a spiritual type of truth, the one that usually falls outside the scope of science blogs. However, this statement in our society has been generalized and applied to any activity that involves a search for something. It is as if we take it as a given that the mere activity of searching will lead to the discovery of that which we are searching for. The problem is: what if we search for something that isn’t there? What if there is nothing to find? What happens then?
Searching for something that we want to find when there is nothing to find can quickly degenerate into the equivalent of finding shapes in the clouds. This is all too obvious, for example, to police departments that want to involve the public in supplying tips on a high profile case. They know that the majority of the information they are going to receive will be false positives, and they are going to need a lot of personnel and resources to chase down leads the vast majority of which will turn out to be false. This phenomenon is seen in all human beings including scientists. I have mentioned before in my blog the cases of the astronomer Percival Lowell who claimed to have observed canals on Mars, which he interpreted to be evidence of an advanced civilization, and of the scientist Rene Blondlot who thought he had discovered a new form of radiation. Invariably, when we are searching for something that is not there, and we want to find it, we will tend to find it one way or another. Because of this, scientists regularly use special experimental designs in those studies that rely to a great extent on the evaluation of the results by a human observer to avoid making this mistake.
As many studies have shown, our perception of reality can be strongly influenced by our expectations. But these expectations are not limited to something we are looking for. In fact, the very way we process the information we receive minute by minute in everyday life, even when we are not consciously searching for something, is influenced by our expectations. Our perception of reality is not passive. We subject the process of making sense of the inputs that are relayed to our brain by our senses to many filters, and some of these filters are made up of complex social and psychological premises that are a product of the interaction between our experience, our environment, and our genes. For example, new evidence that shows, yet again, that the Earth’s climate is warming, or that vaccines are safe, or that evolution is true, will be perceived differently by a regular person as opposed to a climate change denier, a person opposed to vaccination, or a creationist, respectively.
But why does our brain function based on a system where expectations can hinder the correct appraisal of reality? The answer is that we do this to make sense of the world around us. Once we have decided that our environment operates based on a certain set of rules that give rise to certain patterns, we will seek and find these patterns in the information we receive from our senses, and discard or ignore the rest. This approach is actually useful. It serves as a way to reduce the seemingly vast complexity of the world that surrounds us to a simple set of premises that will generate certainties on which we can base our actions. The downside of this approach, of course, is that we tend to blind ourselves to the perception of things that do not fit our expectations, and the flip side is that we see things where there is nothing to see. This is why conspiracy theorists keep on finding evidence of conspiracies even when no such evidence exists.
So the saying “seek and you shall find” should probably be amended to:
“Seek and you shall find, and if there is nothing to find, you shall make it up!”
Such is the complexity of the human mind.
Perception image by Geralt from Pixabay is free for commercial use.
A long time ago, back when I was a young teenager, my mother bought the book The Exorcist by William Peter Blatty. This book is about the possession of a girl by a demon and her subsequent exorcism. My mother placed it in our book room. However, she thought that it contained things that were not appropriate for my age. So she called me over and explained that she had bought this book, but she did not want me to read it — Mom, really? Needless to say that as soon as I had a chance, I made a bee line for the book room and read the book: bad idea. The descriptions and the language in the book terrified me. I could not get the images and words out of my mind, and for about a week I did not sleep well. As soon as I turned off the light every sound and shadow in the room acquired a sinister nature, and I was be consumed by fear. At times I thought I saw things moving about my room. At times I thought I heard voices. It was really creepy, and the worst thing is that I could not tell my mother because she would figure out I had read the book! However, by the time I got to see the movie based on the book, I had gotten my act together enough to see the film without losing my composure.
Fast forward 20 years or so. I studied biology in college and later obtained a Ph.D. in Nutrition with a major in Biochemistry. I learned the ways of science and how matter and energy in this world operate based on specific physical, chemical, and biological principles. I published a weekly newspaper column entitled “The Scientific Truth” that dealt critically with pseudoscience and the paranormal. I still remembered my Exorcist-induced week of fright, but I interpreted what had happened to me under a whole new light.
What happened to me was due to the fact that human perception is not a passive event. We do not merely take input from the environment to directly construct our perception of the world around us, but rather we are constantly interpreting this input based on a set of parameters that the brain applies to make sense of reality, and these parameters can be changed by experience. That day so many years ago, I was exposed to very strong stimuli that reshaped the perception of reality by my brain. The noises and shadows in my bedroom at nighttime had not changed from the way they had always been, but my brain reinterpreted them in light of the new information obtained from reading the book and made me fear them. Fear is often a useful emotion that can keep us from harm, but when fear is too intense or not based realistic premises, it can have paralyzing and unhealthy effects.
I reasoned that my fear that night was a result of ignorance. Despite the claim that Blatty’s book was based on a real exorcism, not a single case of demonic possession has ever been conclusively demonstrated to be anything but mental illness. In the exorcisms that have taken place, objects don’t fly, lights don’t flicker, bodies don’t levitate, etc. The occurrences taking place in these events are within the realm of what’s possible when people experience mind-altering diseases. My fear that night was unwarranted. I felt a bit silly for having experienced it at all, and rolled my eyes at the gullibility of my former younger self.
So it happened that I found myself carrying out research that involved periodic trips to a faraway town by the sea, where I worked at a small research station. In one of these research trips, I was the only scientist working at the station. After I had been working for most of the day, there was a failure in the electric grid and the lights went out towards the late afternoon. Since my workroom didn’t have any windows, and I just had a rudimentary flashlight, I decided to call it a day. I had a quick dinner and headed into town right before dusk. There I came upon some of the local fishermen who had gathered around an improvised log fire. A couple of them worked with the research station, and I sat with them. The fishermen shared some of the local stories of the town’s past, and then as it got darker, they started telling ghost stories!
For the next two hours next to the flickering light of the fire and under a sky faintly lit by a crescent moon, I heard these adults talk about things they had seen or heard during their lives. The lore included screams and moans of unknown origin coming from the mountains adjacent to the town, strange vaporous figures floating around at night, things hovering over the sea waters or lurking just beneath them, open graves with missing corpses at the local cemetery, the doom that had befallen some people cursed by an alleged local witch, etc. I alternated between being amazed and amused. I didn’t know to what extent these people were exaggerating their stories, but most of them seemed very convinced that they were true. I knew that groups of skeptics had been systematically investigating one claim after another of ghosts, witches, paranormal occurrences and whatnot for decades finding nothing that could not be explained by science. However, I did not want to be disrespectful. These fishermen were bonding and apparently having a good time, so I kept my mouth shut.
After the group dissolved, I went back to the research station. It was quite dark and the silver glow of the moon gave the surrounding landscape a surreal pale phosphorescent tinge. Inside the research station it was pitch black and the faint light of my flashlight barely helped me make my way along the corridor that led to my bedroom. The shadows created by my flashlight seemed to move in strange ways, and I became aware of noises that I didn’t remember hearing before. Was there something lurking in the darkness beyond the glow of my flashlight? Was it moving towards me? The same sensations I had experienced 20 years ago came back in full force. This time, I was older. I knew better. I was not ignorant. I was not gullible, and yet, I was caught again in the grip of fear. Inside my brain an ancient program had been activated. A program derived from our animal ancestors, created by the forces of evolution, and amplified by superstition and ignorance. A program that for thousands of years made us fear what lay beyond the cave entrance or the perimeter of the campfire, even if there was nothing there. And I could not shut it down!
Thankfully an emotion stronger than fear came to my rescue: anger. I became extremely angry because, although I understood exactly what was happening to me, I was not able to control it. As I made my way along the dark corridor to my bedroom, I clenched my fist, waved it at the darkness, and screamed, “I’m a scientist”! This sounds stupid today, but that day it worked. I was able to counteract my fear with sheer outrage at how silly I felt at being manipulated by my own brain. After a couple of hours of more fist clenching, I was able to force myself to sleep. Next day the electricity returned, and that night I fell asleep uneventfully.
What I understood after this experience, is that mere knowledge and/or conviction that something does not exist and can’t harm us does not immunize us against fearing it. We have all grown up within a culture that through oral stories, movies, books, and other means has conditioned our brains to accept at a very primal level that things like demonic possession, ghosts, and other fictitious entities or occurrences exist, can harm us, and should be feared. This conditioning can at times manipulate us like puppets and make us feel things that we are not justified in feeling from a rational point of view.
But at least now I understand this: I am a scientist.
The cover of the book The Exorcist and the poster of the movie are copyrighted and used here under the legal doctrine of Fair Use. The ghost picture by Alexas_Fotos is from Pixabay and is licensed for public use.
In his excellent 1994 book, The Astonishing Hypothesis, the late Nobel Prize winning scientist, Francis Crick (co-discovered of the structure of DNA with James Watson), put forward a hypothesis that boggles the mind. He wrote:
“You, your joys and your sorrows, your memories and your ambitions, your sense of personal identity and free will, are in fact no more than the behavior of a vast assembly of nerve cells and their associated molecules.”
He claimed that this hypothesis is astonishing because it is alien to the ideas of most people. This is presumably because, when it comes to our mind, we believe that there is something special about it. Clearly the mind is more than the product of the activity of billions of cells, no? Exalted emotions such as love and compassion and empathy or belief in the divinity or free will cannot just be a byproduct of chemical reactions and electrical impulses, right? But why would that be the case? Consider an organ like the intestine. It’s made up of billions of cells that cooperate to produce digestion. Most people will agree with the notion that the intestine produces digestion. So, if we can accept that the cells that make up the intestine produce digestion, why can’t we accept that the cells that make up the brain produce the mind?
Let’s just touch on something simple, but that nevertheless goes to the very core of our notions of free will and consciousness. Consider an action such as performing the spontaneous motor task of moving a finger to push a button. In our minds we would expect that this and other such actions entail the following sequence of events in the order specified below:
1) We become aware (conscious) that we want to perform the action.
2) We perform the action.
But what goes on in our brains even before we become aware that we want to perform the action? Many people would guess: nothing. Whatever brain activity occurs associated with the action must logically occur after we become aware that we are going to perform the action. After all, how could there possibly be nerve activity associated with an action that we are not even yet aware that we want to perform?
Warning! Warning! - Insert blaring alarms and rotating red lights here - Fasten your existential seat belts because this ride is about to get bumpy!
In 1983 a team of researchers led by Dr. Benjamin Libet carried out a now famous experiment to evaluate this question. The researchers recorded the electrical activity in the brains of test subjects which were asked to perform a motor task in a spontaneous fashion, and they also asked the subjects to record the time at which they became aware that they wanted to perform the task. The surprising result of the experiment was that, while the awareness of wanting to perform the task preceded the actual task as expected, the electrical cerebral activity associated with the motor task performed by the subjects preceded by several hundred milliseconds the reported awareness of wanting to perform the task! This amazing experimental result has been replicated by other researchers employing different methodologies.
One study employing magnetic resonance to image brain activity stablished not only that the brain activity associated with the task is detected in some brain centers up to 7 seconds before the subject becomes aware of wanting to perform the action, but also that decisions based on choosing between 2 tasks could be predicted from the brain imaging information with an accuracy significantly above chance (60%). Delving even deeper into the brain, another group of researchers recorded electrical activity from hundreds of single neurons in the brains of several subjects performing tasks and found that these neurons changed their firing rate and were recruited to participate in generating actions more than one second before the subjects reported deciding to perform the action. The researchers could predict with 80% accuracy the impending decision to perform a task, and they concluded that volition emerges only after the firing rate of the assembly of neurons crosses a threshold.
The interpretations of these types of experimental results have triggered a debate that is still ongoing. The most unsettling interpretation is that there is no free will (i.e. your brain decides what you are going to do before you even become aware you want to do it). However, there are many critics that claim that there are technical flaws in the experiments, that the data is being overinterpreted, that the electrical activity detected is merely preparative with no significant information about the task, or that it is a stretch to extrapolate from a simple motor task to other decisions we make that are orders of magnitude more complex. In any case the question of whether free will exists is in my opinion irrelevant because our society cannot function under the premise that it doesn’t. What interests me from the point of view of the astounding hypothesis, is the possibility that the awareness of wanting to perform an action before we perform it is merely an illusion created by the brain.
This notion is not farfetched. As I explained in an earlier post, the brain creates internal illusions for us that we employ to interact with reality. Colors are not “real”, what is real is the wavelength of the light that hits our eyes. What we perceive as “color” is merely an internal representation of an outside reality (wavelength). The same goes for the rest of our senses. As long as there is a correspondence between reality and what is perceived, what is perceived does not have to be a true (veridical) representation of said reality. Consider your computer screen. It allows you to create files, edit them, move them around, save them or delete them. However, the true physical (veridical) representation of what goes on in the computer hard drive when you work with files is nowhere near what you see on your screen. This is so much so, that some IT professionals refer to the computer screen as the “user illusion”.
So, much in the same way that the brain creates useful illusions like colors that allow us to interact with the reality that light has wavelengths, or the computer geeks create user illusions (file icons) that allow us to interact with the hard drive, could it be that the awareness of wanting to perform actions, in other words, becoming conscious of wanting to do something, is just merely an illusion that the brain creates for the mind to operate efficiently?
We are still in the infancy of attempts to answer these questions, but what is undeniable is that the evidence indicates that there is substantial brain activity taking place before we perform actions that we are not even yet aware we wish to perform, and that this brain activity contains a certain degree of information regarding the nature of these actions. As our brain imaging technology and our capacity to analyze the data gets better, will we be able to predict with certainty what decision a person will make just by examining their brain activity before they become aware they want to make the decision?
It’s too early to tell, but from my vantage point it seems that so far Crick’s astonishing hypothesis is looking more and more plausible.
The image of the cover of the book The Astonishing Hypothesis is copyrighted and used here under the legal doctrine of Fair Use. The Free Will image by Nick Youngson is used here under an Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license.
The title of this post is a reworking of a philosophical argument originally formulated to address the possibility that things don’t exist unless they are perceived. The statement in its reformulated form posits a scientific question regarding the nature of perception.
In this post I will be writing about the very basic first order perception of reality that is relayed to us through our senses, not the complex cultural, social, emotional, psychological, and many other -al aspects of human perception. Many people would like to think that our perception of the world around us is a complete and true representation of reality. However, scientists have studied the phenomenon of perception for many years and they have come up with some amazing findings.
We perceive the reality that surrounds us through our senses. These traditionally have included sight, smell, taste, touch, and hearing. On top of these we have additional senses such as the ability to perceive heat or cold, the ability to perceive noxious stimuli (pain), and the ability to perceive acceleration and balance, among others. Each of these senses detects aspects of the world around or inside us and is associated with certain receptors in our body. Despite all that you may have read in sensationalist publications, no claim of extrasensory perception (ESP) has ever been validated. To perceive an aspect of reality, we need to have a receptor in our bodies that will detect it, and one of the consequences of this is that if we don’t have said receptor, we will not perceive it.
From studying other organisms in our planet we have learned that their perception of reality is different from ours. For example, a human, a dog, a cat, a bird, a snake, and a butterfly can look at the same image and perceive it different ways. And this example only covers the sense of sight. Part of the reason this is the case is that other living things have receptors that we lack. Many snakes can “see” heat emission in great detail, which allows them to identify a prey or a predator in absolute darkness. Various organisms, including species of insects, birds, fish, and mollusks, can detect ultraviolet light. Migratory birds and other animals can detect magnetic fields, which allow them to navigate accurately following the Earth’s magnetic field on long treks. Sharks, rays, and skates, and other species can detect weak electric fields, a sense that they use to communicate or detect prey. Insects such as locusts and bees can see polarized light and use it for navigation. Some species of shrimp can detect ionizing radiation.
The above examples point to the existence of hidden aspects of reality that are beyond our experience, and indicate that our perception of reality is not complete. It must be acknowledged, however, that we have been able to compensate for our limitations with our intellect. We can build devices such as infrared or polarized light glasses, compasses, Geiger counters, and other type of detectors that can allow us to perceive or at least measure and exploit these hidden realities. In fact, we have gone beyond that and developed devices capable of perceiving realities that no other life form in our planet can perceive such as imaging the inner structures of our bodies and cells, or detecting gravitational waves produced by colliding black holes.
But, even if our perception of reality is not complete, isn’t what we do perceive an accurate representation of said reality? Our brain utilizes the information relayed by our senses to form a representation of the reality around us; however, this representation is not necessarily true. Everyone, for example, has seen the spokes of the wheel in a moving vehicle slow down, become stationary, and even begin spinning in the opposite direction. There are situations in which our senses can fool us, and many such illusions have been catalogued and even used in art. However, it can be argued that, despite these exceptions, in the majority of cases our perception of reality must be essentially true; otherwise life would not be possible.
There is no question that our perception of reality must correlate with reality enough to make life possible. However, this does not mean that our perception has to be a true representation of said reality. Scientists have performed simulations pitting true (veridical) perceptions of reality against utilitarian ones where not all aspects of reality are perceived, but rather just those that make life possible with the least expenditure of energy. In these simulations, the utilitarian perceptions won out in the long term. To understand this concept, consider your computer screen. You have a number of files that show up as icons of a certain shape, color, and pattern. This utilitarian representation of computer files allows for you to efficiently interact with the computer mechanisms that make the creation, editing, archiving, and deleting of files possible, but the actual physical (veridical) reality of what a computer file looks like is nowhere near anything visualized as a desktop icon. Thus we and other living things may be wired to perceive reality in such a similar functional way that stresses utility over veracity.
Now that we have seen that not only our perception of reality is incomplete, but that there is also not a one to one correspondence between our perception and reality or even an overriding reason why it should be accurate, we are ready to answer the question presented in the title of this post.
If a tree falls in a forest and no one is around to hear it, does it make a sound?
When the tree hits the ground it will give rise to compression waves which will propagate through the air and the ground startling nearby wildlife. But if by “sound” we mean the unique perception by our species of these waves, then the surprising answer is: no!
Photograph by the author.