Do humans perceive reality indirectly?
Idealism, representationalism, and realism
Before responding to this question, it is necessary to define what exactly is meant by indirect perception. First of all, it is important to know that there are three main camps of opinion into which people tend to fall in regards to the connection between reality and human perception (Broude 2003). One camp, called idealism, is of the belief that perceptions are completely fabricated by the individual; there is no external reality on which they are based. The second camp, called representationalism (a.k.a. representative realism), believes that perceptions are based on representations of the real world rather than information obtained directly from the world, and people therefore have a distorted understanding of what exists in reality. The third camp, called realism, claims that perceptions are based on a world independent of the person perceiving it. Therefore, direct perception refers to the idea of realism -- that perceptions correspond directly to the external world -- and indirect perception refers to the idea of representationalism -- that perceptions are not of the world itself, but of representations of it, within the mind.
Because the concepts of direct and indirect perception can only apply to a situation in which there is some outside world to be directly or indirectly perceived, the question is moot for those in the idealist camp. However, the concept of idealism does not hold up very well under scrutiny. It seems clear that there is a difference between what is in the real world and what is purely imagined (Kelley 1986). As David Kelley says, "Each thing I perceive has an identity, it is something. And it is what it is, not what I make it. These things before me are not at all like the objects of imagination, which I can shape to suit myself" (Kelley 1986, p. 31). While the objects created by the mind can be acted upon in any way and changed at a whim, the objects in the outside world are not so malleable; they are restricted to certain laws of physics. For instance, it is not terribly difficult to imagine oneself in a physically impossible situation, such as walking straight through a pane of glass, the glass parting to let one through and closing again behind one. If one were to try doing this in the real world, however, the glass would stay solid. Either the person would run into it and be stopped, or push through and break it into pieces. While this cannot conclusively prove that the outside world does exist, it seems like an unlikely situation to have been invented by the mind. After all, what would be the purpose of separating the supposed internal from the supposed external, and what would determine which things the person interacted with in the "outside world" versus the things he/she “imagined”? There do not appear to be any logical reasons for having invented any impossibilities such as this for ourselves. In the same vein, it seems like quite an involved process to have gone about inventing sensory systems -- visual, auditory, olfactory, and so on -- if there is not really anything for us to sense at all.
What is a representation?
Assuming that idealism is not a realistic explanation of perception, the two options left are representationalism and realism, or indirect and direct perception. At this point, it will be helpful to establish just what is meant by a representation. According to Merriam-Webster Online (2003), one definition of the word "represent" is "to serve as a sign or symbol of ". So, a representation is a sign or symbol of something else. In this case, the word “representation” will also be taken to mean a construction of something new in the brain (Broude 2003) to symbolize something preexisting in the world. The term also implies that the thing a person consciously perceives is not actually in the world, but rather in the brain.
It can hardly be argued that there is absolutely no representation taking place in the brain. Even a realist would have to concede that, for example, a desk I perceive is not actually in my brain. Any judgment I make about the desk is made about the pattern of firing neurons in my brain that I interpret to mean there is a desk in front of me. This pattern of firing neurons is a representation of the desk, not a desk itself. Additionally, there are representations in the case of memories, judgments, and fantasies. In these cases, it is apparent that the things one is thinking about do not physically come up in front of one. Since what a person perceives is not physically there in front of him/her in these cases, these sorts of perceptions can be taken as representations, as described in the preceding paragraph.
Memories and judgments are different sorts of perceptions of reality that can be considered representations, but there is still the case of using the sensory systems (visual system, auditory system, and so on) to perceive. Memories and judgments are perceptions of the past (however recent), and so the focus will now shift to perception of objects in the present. Conceding that patterns of neuronal firing do comprise one sort of representation, I will narrow the definition of representation. From here on, a representation will be taken to mean some firing pattern, fabricated by the brain and based on information from the perceptual systems, which is what humans are consciously aware of perceiving.
Perceptual mistakes
According to Immanuel Kant (Broude 2003), the perceptual systems must be physically set up somehow, and they must work in a certain way. Because of this, the image of the world that people perceive cannot be completely true to the actual objects in the world; they must be distorted in some way. There have also been other pieces of evidence suggested. For instance, there are numerous optical illusions in which the person will perceive color, shape, or movement when there is none. People with amputated limbs feel phantom pains (Broude 2003). People who are very sick, mentally ill, or using certain drugs can hallucinate. To put it succinctly, humans often make perceptual mistakes.
David Kelley's response (1986) to the idea of perceptual mistakes is fairly straightforward. He points out that there is a difference between what is being perceived and how a person perceives it. Perceptual systems may be inconsistent, but this does not mean that what the person is experiencing is not reality; it simply means that the perceptual systems are not perfect. This would be Kelley's response to the examples of optical illusion, phantom pain, and hallucinations. There is no reason to believe that humans actually create the things they perceive; they simply process the things that are in the external world. In response to Kant's claim that the world is perceived in a distorted way due to the fact that humans have perceptual systems with which to sense it, Kelley would argue that there is no such thing as distorted perception of the world. There is not some single, innate way that the world is supposed to be perceived -- rather, the things in the world emanate certain types and quantities of energy that are interpreted in different ways by different perceptual systems.
The evolutionary standpoint
Beyond Kelley's claims, there is a logical argument against representationalism from an evolutionary standpoint. Evolution tends to create organisms with characteristics and behaviors that are fitting to their environments. Those organisms that have some characteristic that makes them more fit live, while those with less fit characteristics die off. Evolution takes place across an extremely long time span, and most complex systems do not evolve all of a sudden, but rather gradually, building up over time. Thus, there tend to be good reasons for certain behaviors or characteristics lasting while others die out; they need to somehow help the organism survive. Given this background, it is highly unlikely that representation would have evolved in human beings. It would have to have somehow helped humans survive, and it would have to have formed gradually, surviving each step of the evolutionary process. If anything, however, one would think that seeing the world through representation would make humans less fit -- if one perceives the world in a distorted way, one is more likely to make incorrect judgments about it that could lead to death. Furthermore, even if it did not specifically harm humans, it is difficult to conceive of any way in which it could be helpful.
Given all of this information, one can conclude that human beings do perceive the world indirectly -- that is, as indirectly as anything else that senses the world -- insofar as patterns of neuronal firing can be taken to represent a given idea or object. One can also be considered to perceive the world indirectly in that one does have thoughts, memories, and so on about things that are not physically near one when one thinks about them. However, if one considers a representation to mean a firing pattern of the brain created to symbolize some other firing pattern that occurred as a result of the energy coming into the perceptual systems through the external world, it is clear that humans do not perceive reality indirectly. The evidence against realism amounts to a misunderstanding of the difference between what humans perceive and the systems they use to perceive it. Beyond the fact that there has been no convincing evidence for representationalism, it is an evolutionarily illogical phenomenon.
Bibliography
Broude, Gwen. Professor of cognitive science. Lecture on January 23, 2003 at Vassar College.
Kelley, D. (1986). The Evidence of the Senses. Princeton: Princeton University Press.
Merriam-Webster Dictionary Online. http://www.m-w.com/cgi-bin/dictionary. Retrieved February 12, 2003.