I have tried to communicate a fact to my readers regarding the nature of our perception of reality in some of my blog posts, but judging from some of the replies I’ve received, I don’t seem to have gotten the point across. This may have happened because my explanation was one of several ideas I was writing about. So I’ve decided to make the perception of reality the main topic of this post. Let’s go.
As the title of this post implies, what you see, hear, smell, taste, and touch is fake. What do I mean by fake? What I mean is that what you see, hear, smell, taste, and touch are not physical realities that are “out there” and are independent from you. And here let me clarify that I am not being flippant or just “expressing my opinion”. What I am telling you is a fact that is accepted by scientists and was discovered a long time ago. This is old news.
How can this be? Is life then a dream or some other sort of mystic stuff? The answer is “no”. Let me explain.
The brain detects the reality around us through receptors present in our eyes, ears, nose, mouth, and skin. When these receptors are triggered by outside stimuli, they generate an electric signal that travels by the nerves to our brain. So what our brain receives is not light, or sound, or smell, or taste, or tactile signals. What the brain receives is just electric signals. Once these signals arrive to the centers of the brain responsible for perception, these electric signals are filtered, organized, and integrated to CREATE perception. Did you notice that in the previous sentence I put the word “create” in caps and underlined it? Yes, the brain generates a perception for us that is very different from the physical reality present “out there” that generated the signals which were detected by the receptors in our eyes, ears, nose, mouth, and skin. Let’s see how.
We see color, but color is just a brain-generated representation of the wavelength of the light rays that strike our eyes. The physical reality out there is that light rays have different wavelengths, but we don’t see wavelengths. In fact, if it were not for science, we would not know that light has a wavelike nature! What the brain does is create an internal representation of these different wavelengths where we perceive short wavelengths as purple and long wavelengths as red.
With regards to hearing, it’s the same thing. The mechanical perturbations in the air around us reach our ears as compression waves, and by pretty much the same process as vision the brain generates an internal representation of these waves where we perceive short waves as high pitch sounds and the long ones as low pitch sounds.
In the case of smell and taste, the receptors in our nose and mouth detect the chemical structure of compounds in the air, food, or drink, and the brain generates the different fragrances and flavors we perceive. The reality “out there” is not fragrances and flavors, but merely chemical structures.
Finally, there are receptors in our skin that send the brain a signal when, for example, they detect a difference in temperature. This signal is integrated by our brain to generate the sensations of hot or cold that we experience. The reality “out there” is differences in heat content, but we perceive this as “hot” or “cold”. Something similar happens for other skin sensations such as the compression of our skin (which we perceive as pressure) or the damage to our skin (which we perceive as pain).
This is why, as I stated in the title of this post, everything you perceive is fake. What you perceive is not a real (veridical) representation of the reality “outside” of you. And of course, the way our brain perceives reality also affects vastly more complicated things such as the emotions we experience, the convictions we have, or the actions we take.
But, if this is true, how can we even function?
The answer is because there is a correlation between the reality “out there” and our perception of it. And we know this correlation is high because life would otherwise not be possible (if you don’t recognize the edge of a cliff as you approach it, you will die). This is a situation analogous to when you work with a computer. You create and move and delete files all the time in your screen, but the physical processes taking place in your screen are very different from the physical processes that are taking place in the hard drive of the computer (so much so that some people in information technology refer to the screen as the user illusion). However, because they are correlated, it works. Thus, at the level of our basic senses (sight, hearing, smell, taste, and touch), our perception of reality although fake, is not false.
So, if there is a correlation between the sensations that our brain generates and the reality “out there”, why should this even be an issue worthy of consideration? The reason is that the correlation between reality and what we perceive is not 100% percent. There are many well-known illusions that can fool our senses because they exploit this disconnect between reality and perception. But at more complex levels, there are many biases in our perception of reality that can lead us to filter said reality and distort our perception of it to the point that it becomes false. For example, many people still accept conspiracy theories such as those denying the results of the 2020 election, the effectiveness of the COVID-19 vaccines, climate change, the 911 attacks, or the moon landing. Others accept false world views such as creationism, QAnon, or the flat Eart.
How our way of perceiving reality can lead to its distortion is an active area of research in scientific fields ranging from molecular neurobiology and cognitive neuroscience to psychology and economics.
"Five Senses" by TheNickster is licensed under CC BY-SA 2.0.