What is reality? Is it what a sane, rational person can perceive with their five senses? Is it something we can observe with instruments and measure? When we talk about something being “real,” what do we mean? Most of us take for granted that the things we perceive with our senses are based in reality, but how often do we stop and think about what is actually happening when we perceive something?
The sun’s gravity produces heat and pressure, causing hydrogen atoms to fuse together. This gives off energy in the form of light, a teeny sliver of which we call visible light. This light travels from the sun to earth. From its perspective the journey is instantaneous, but for us there is an eight and a half minute delay. This light then strikes our atmosphere, where it comes into contact with atoms and molecules which absorb and re-emit the light, changing its direction and frequency. This light can then strike an object within our sight, reflecting off its surface and striking the back of our eyeball. Nerves in the back of our eye respond to the light by sending a signal to our brain, which interprets the impulse. If we are paying attention to what we are seeing, our brain will automatically create an image from the impulse it received and begin the process of categorizing and understanding what we are seeing. When we see this object, our perception is dependent on all of these events coming together to produce a mental image.
With all of these factors coming into play, we have to wonder whether or not this process of seeing is reliable. When we see something, does it correspond to how another sees it? What if the makeup of our eyes is different? What if our brain processes the information differently? What if we were not paying attention and the image came and went without us even recognizing its presence? What about the rest of the electromagnetic spectrum which we cannot perceive with our eyes alone? There is a world of information which we cannot normally perceive, and even our perceiving is suspect.
Our senses and perception have brought us this far in life. Isn’t that proof that our perception is reliable? To a certain degree, this is a reasonable argument. Our senses are adequate for living our lives. But is adequate what we desire? No, we desire more – to see accurately what is true and what is real. “Good enough” is not good enough; we demand to know reality for what it is and not merely how we perceive it. Scientific investigation is a strong answer to this problem of our “seeing but not perceiving.” With scientific instrumentation we can observe the unobservable, making the full band of the electromagnetic spectrum observable to our eyes by converting it into data and sensations which we can understand. But even then we are left with the problem that we are perceiving these only indirectly. We know what color blue is, but what color is 99.1 FM frequency?
To a certain degree it is hopelessly pessimistic to dwell on the limitations of our perception. These are not problems we can solve or obstacles we can overcome. The human eye can only see what it can see and the brain can only interpret what it gets from the senses. But it is incredibly helpful – humbling – to remember that we are so limited. There is a vast amount of information in the universe. There are whole realms which we cannot explore without relying on instrumentation to interpret the data for us. We could talk about distant galaxies, black holes, and dark matter. We might consider quarks, atoms, and other particles. We might even consider the perceptions of the person who is nearest to us at this moment. Though they may be within speaking range of us, their perceptions of the universe are completely inaccessible to us. We cannot know what “blue” looks like to them because we do not share their eyes and brain. So we must remain humble.
Eyewitness testimony is one of the most unreliable forms of evidence. What we see, perceive, and remember – this does not necessarily correspond to what a camera sees or what a receipt or footprint might demonstrate. Yet much of what we believe most strongly relies heavily on our experiences of life and how we perceived them. It may be helpful for us to consider these limitations when dealing with others. Perhaps what they said was not really spoken in a harsh tone. Maybe they did not really roll their eyes at us. We give so much weight to our perception because it has gotten us this far in life. Maybe it would be helpful to question our perception more often – not to live in the ambiguity of never knowing if anything we perceive is reliable, but with less confidence in our own perceptions. We might try having a greater reliance on – and openness to – how others perceive things. And of course an openness to scientific insights can help us greatly.
What do you think? Is our perception reliable? Is it wise to seek out opinions of others to see how they perceive the world? Is science more or less reliable than our own perceptions?