Human senses do not give much knowledge to the world as it really is; they primarily function to create a physical representation of the world that the brain can understand. Human senses can detect and receive true information, but the brain processes this information to attempt to form an image of the world that is coherent, not as it truly is. On the other hand, some people might say that human senses can give us absolute knowledge as the world is; it is just the way that humans organize information that leads to the common thought that what we perceive is not truly what is.
Human senses are, in the most basic of definitions, ways that the mind receives information from the outside world. Whether this is through touch, smell, taste, sight, or hearing, does not matter; it is still information from the outside world, in this case, categorized into groups. This means that what information that is going into, for instance, the eye, is true raw information of the world; it is the world as it really is. The brain does not know this information even exists in its raw form, as processing takes over subconsciously.
Out of processing, comes the physical representation of our world. The operative word in that sentence is representation. Human senses can only give one a representation of the world according to one’s own subject organizational skills and the information gathered by one’s senses. This limitation on knowledge of the true world occurs because the raw information, the world as it truly is, is processed and warped until the human brain can comprehend the information and produce a coherent idea of what is outside of the mind. This processing of information in order to create a coherent world can be seen in many illusions. In the “grid illusion”, the white spots on a black planar grid appear to spontaneously change from white to black. This spontaneous and rapid change in color does not actually happen. What is actually happening is a conflict between the two sources of information, the right and left eye, and a false representation of the world created by the mind’s desire for a coherent world.
When the brain scans the illusion, moving left and right swiftly, the eyes focus on critical points of the illusion, glazing over other parts of the illusion. Thus, the brain, attempting to form a coherent unicolor picture, assumes that the parts of the illusion it cannot gather information from are simply black, like the rest of the picture. However, they are not. Thus, whenever the brain receives information on those assumed parts; the brain realizes that it was wrong in assuming those parts were black and changes the black parts in the physical representation of the illusion to white parts. This process happens rapidly and this results in the consequence of the dots turning from black to white frequently. Thus, the illusion of the spontaneous changing of color of dots from black to white and vice versa is caused by the processing of the brain trying to create a coherent version of the world.
In addition, the senses receive this pure and true raw information rather haphazardly. Thus, the information gathered is also unreliable when concerning knowledge about the true world. For example, the rods and cones contained within the cornea of the human eye are used to detect light and color, respectively. However, when the cornea is not exposed to copious amounts of light for a long period, the cornea’s rods become adapted to the darker environment. Then, when the cornea is introduced to a light-rich environment, the cornea receives this information as being extremely bright, to the point where there is no way for the cones to function, and thus there is no color. In this information gathered from the true world, there is only extremely bright white light. However, in many cases, this is not true information; the light-rich environment is not solely comprised of bright white light. That is simply a misconception caused by the cornea’s unreliability. However, this unreliability in the cornea only lasts for a limited amount of time, three to four seconds maximum, because the brain realizes the problem and fixes it. Even though the unreliability is short lived, it is crucial in the way it portrays the haphazard way raw information is gained through perception.
Therefore, because the senses are also unreliable in how they gather this true information, there is uncertainty contained within the true information the brain receives. Then, when the brain processes this information, this uncertainty is greatly increased because the brain is warping already deformed information in an attempt to reveal a representation of the world. Overall, the end of the processing comes a flawed version of the world.
The problem of human organization becomes much more obvious if the counter thesis is more greatly analyzed. For example, the cornea receives the information of a beam of light with the wavelength of 494 nanometers. This wavelength is very near the color of violet while still being within the boundaries of blue’s wavelength. The brain then processes this information; the wavelength of 494 nanometers that is, and then organizes it by saying that the light is blue. All this information is correct, however there is dispute between what the colors truly are. This is because colors are learned and thus color names are not a priori, but instead are a posteriori. Thus, when the two people come together and try to organize the same light by color, problems occur as their brains could have organized the colors differently because they each learned the colors differently. Thus, it is not how the world truly is that cannot be seen, it is simply the way humans try to organize the true world that actually cannot fit the entirety of the world. It is the subjectivity of the a posteriori organization skills that cause the downfall of perception.
This is a correct statement, the world can be understood through perception. What is actually causing people to not have true knowledge of the world is the organizational skills they learn after they are born. However, organization is a completely a priori phenomenon. For example, babies organize colors very simply, black vs. white. They organize black into association of nothingness and white into association with existence. Therefore, human kind has a need to organize and categorize the information against and with previously assumed information to understand the world. Thus, while it is true that perception can be used solely to gain knowledge about the world as it really is, the problem arises whenever one attempts to organize the information into a coherent image. This is a slight problem because unprocessed perceptual knowledge is useless as it is random information scattered around the brain.
All in all, human senses cannot fully give us knowledge about the world as it really is. This is due to the haphazard way the physical receptors of our senses gather information, the heavy processing of information to form a coherent physical representation of the world, and a differing a posteriori organizational skills, which are used to come to the coherent representation of the world. However, some people do believe that knowledge of the world can be gained solely on the perceptual information gained from the perception organs.