Human beings certainly do not perceive reality like it really is. This fact is immediately evident through both experiential and experimental evidence. If our senses do give us information about the way things truly are, then how is it that if two people go to a concert, they can walk away with different reviews? Was the concert good or was the concert bad? Which one better reflects reality? Furthermore, what explains the phenomena experienced by people who have had brain injuries? Oliver Sacks has written entire books on the subject, including “The Man Who Mistook his Wife for a Hat.” Does a person such as this with visual agnosia experience reality? What about people with synesthesia? Is the key of Eb blue, or is it not?
Perhaps the single most obvious way that we can know that we are not always experiencing reality as it truly is, is by observing the different ways people interpret and experience the same event. There are any number of examples of this, but for the sake of simplicity, let’s use the example of light and dark. Say, for example, that a married couple work opposite shifts, that is, one person works a 9-5 day (person A), and the other works nights (person B). Person B comes home from work at 5am, while Person A is still sleeping, and turns on the lights. Person A exclaims “it’s too bright! Turn the lights out!.” Person B thinks it’s too dark without the lights. Which person’s experience is reflecting reality?
One may argue that everyone’s experience of reality is filtered through subjective experience, but the experience of reality is still present. For instance, it could be argued that the reality of the situation, which both person A and person B experienced, is that a light was turned on. The qualia of the experience may be different for the two people- person A thought the light was too bright, and B thought it was ok- but the reality of the moment was mutually understood.
This counterargument sounds solid at first, but falls apart under closer examination. First, these qualia that are dismissed as insignificant form a major part of human experience. As a matter of fact, it could even be argued, as Chalmers and others have through the p-zombie thought experiment, that true consciousness depends on the subjective. If this argument is accurate, then the very definition of consciousness is dependent upon qualia. Since we’re interested in the experience of sentient humans, there can be no such thing as an experience that is not filtered through the subjective. Consequently, our experiences are not impartial, and “the light is too bright” IS someone’s perception of reality, and a biased one at that.
Also, this counterargument does not take into account brain-states that might alter the way that input is perceived. A simple example would be a person who is color-blind. Is that person experiencing reality? Or, by extension, we could look at humans in general. Our eyes only see a certain segment of the light spectrum, and our ears only hear a small part of the auditory spectrum. We’re missing a significant amount of “information” about the universe around us. How can we purport to say we are experiencing reality when we only detect a portion of it? This argument is even more applicable to those with altered brain states, such as intoxication, or even something as simple and common as synesthesia.
Let’s use the example of hallucinogens. If a person takes LSD (one could argue this is a form of pharmacologically-induced synesthesia), then have they abandoned reality, or are they more in tune with it? If a person is able to “see” the pitch Eb, such as people either on LSD or with synesthesia might, then are they tapping into a part of reality that is hidden from the rest of us, or is that a distortion of reality? How do we know? What about all the strange cases from Oliver Sack’s books? He presents a litany of cases where patients’ experiences of reality are changed by trauma or peculiarities in their brains. If our experiences and perceptions can be so easily influenced or changed, then what does that say about how dependable they are to begin with? And to take a functionalist perspective, since it is not possible to manually create the exact same brain-states in different people, how could we ever hope to produce the same experience of qualia between two different people, especially when one is tripping and the other is sober?
Finally, this entire question may be premature. We still do not understand exactly what reality is, so how can we know if people are able to perceive it? Since the discovery of quantum mechanics, we have become increasingly aware of just how much we don’t know. We still don’t know, for instance, exactly what makes reality real. For instance, how could it be that matter could spontaneously pop in and out of existence? Classical physics can’t explain that for us. If our sciences fail to inform us about well-observed phenomena, then how can we say that we even know what reality is?
The same argument could be made for consciousness itself. There are several takes on the Philosophy of Mind, and none, at the moment, seem to really have the upper hand. Does consciousness occur when neurons fire at 40 hertz, as Crick and Koch proposed? Or was Bogen right when he said that it’s all about quantum physics, and the brain’s ability to tap into that quantum weirdness? Or are the still stranger theories, such as that consciousness pervades the entire universe, correct? Before we can even get at the question of whether or not we can accurately perceive reality, we must know what reality is and what exactly it is we’re saying is doing the perceiving.
One may argue that all that reality is is simply the way that one’s brain interprets the stimuli that it encounters. If this is true, then reality is not a fixed thing, but rather a malleable substance that is dependent on the peculiarities of each person’s brain (or whatever it is we believe is doing the perceiving). This argument reminds me of a brain in a jar, or the movie The Matrix. We believe that we experience things as they are, but the truth would be that we are nothing more than a brain in a jar, and reality is composed for us there.
The problem with this argument is that there is very little credible evidence that that is the case. Experientially, we seem to share a common existence. Two people can see a car, and later both agree that what they saw was a red toyota, or what have you. Two people can hear a piece of music and agree that it was slow, or sad, or joyful. So, there must be something “out there” that we are all perceiving, though admittedly our experiences are filtered through our own biases.
Clearly we do not experience a pure representation of reality. The human brain, and consciousness itself, are too complex and biased to allow for such an experience. If we are to understand what reality really is, it will have to be through instruments far more objective than the human mind.
“Quantum Approaches to Consciousness.” Stanford Encyclopedia of Philosophy. Stanford University, 2004. Web. 2 Dec. 2014.