Perception versus Knowledge

When we look at an optical illusion, we understand that what we see is not actually moving, however much circles may seem to spin or lines may seem to join together. This is why the design is an illusion—it fools the eye into seeing something which does not (and which the brain knows does not) actually exist. In such an instance, we cannot trust our eyes to relate true information to the brain. This experience demonstrates the difference between perception and true knowledge.

Perception and knowledge are both ways for our brains to receive and absorb information about the world around us. Whether or not this information is true, it enters our brains, where we then decide upon its validity.

Perception is the acquisition of information through the five senses. Perception is concerned with the qualities or form of an object or idea, rather than the deeper substance. However, our eyes, ears, nose, mouth, and nerves can be fooled into misinterpretations; also, the electrical signals sent to the brain from the rest of the body can be replicated, tricking us into believing that we “know” something to be true when in fact it is false. When we dream, the realities created inside our heads often fool us into believing that we are experiencing reality—what we perceive seems incredibly realistic; not until we wake up do we understand that we were dreaming. Similarly, how can we be sure that this life is in fact reality, and not simply another level of dreaming? Based on perception alone, we cannot be sure. A perfect example of this is given in the movie The Matrix. In this movie, human beings believe that they are living in a world very similar to the world in which we live today. They see, hear, smell, touch, and taste this world and do not question its reality. However, in actuality, human beings are enslaved by machines, controlled by signals which are fed into their brains and nervous systems in order to make them feel as though an elaborate computer program, the Matrix, is real. When exposed to the real world, Neo, a computer hacker living in the Matrix, has difficulty believing that the real world is not a dream itself. Though he is shown that the Matrix is not reality, theoretically Neo cannot be perfectly sure that the world outside of the Matrix is real either because he must again rely upon that which he perceives. This concept is very similar to Plato’s theory of shadows on a cave wall. The idea is basically that to a person who for his entire life has seen nothing but the shadows of puppets reflected on a cave wall, these shadows will seem to be reality—they will be perceived as the most realistic thing which such a person has experienced. But only by getting up and walking out of the cave can one become aware of the real world. Both this concept and the ideas expressed in The Matrix demonstrate the unreliability of perception as a means of obtaining information.

In contrast to perception, knowledge comes with deep thought and is concerned with reality which cannot be easily grasped. In order to truly know something, one must comprehend more that can be seen at first sight—one must understand substance, not just form. Knowledge, therefore, cannot be obtained through perception. Rather, knowledge is better obtained through intuition or understanding.

Intuition is knowledge which essentially comes from within us—it is an instinct or “gut feeling” which is not necessarily supported by reason and fact but which we nonetheless accept as true. Intuition is not based on perception and therefore occurs separately from it. Religious beliefs are often based mainly on intuition rather than concrete evidence proving the existence of a God. The legitimacy of intuition is debatable, as sometimes our “gut feelings” can be incorrect or contradictory to logic but, compared to perception, intuition is much less capable of being corrupted by outside forces.

Understanding is a form of knowledge based on logic, the systematic reasoning which allows us to start with one bit of knowledge and glean from it other information. Whereas intuition often comes to us instantaneously, understanding is a longer process which must be carefully thought through. Additionally, intuition does not require fact as a starting point, while logic must necessarily be based in at least one accepted fact from which other ideas can be reasoned. Because understanding begins with an idea or fact, it does not need to be rooted in physical phenomena and therefore occurs separately from perception. Though we may make observations that support our logic or we might base our logic in that which we perceive, these perceptions do not need to be an essential element of understanding.

Science and math are both based on logic. In geometry, for example, before one can begin learning how to write proofs and define complicated terms, one must begin with three basic “undefined” terms: point, line, and plane. These terms form the basis of all of geometry; we assume that we understand them and then use them to create new ideas. Logic is generally accepted as the most valid way to acquire knowledge, yet even logic is flawed: one false assumption or flawed argument will destroy the validity of the conclusions reached. And false assumptions are easily made—even assumptions based on careful research and experience can be faulty. One such example is the concept of Lamarckian evolution, or the idea that organisms can pass on to their offspring characteristics acquired during their lifetime. Though evidence seemed to point toward this theory, and Lamarck based his later findings off it, it was eventually proven to be false.

The philosopher Descartes saw the importance of logic and used it to build his philosophy. Beginning with systematic doubt, he based his philosophy off the one thing he was sure of--he was thinking, and therefore he must exist: “Je pense donc je suis,” or “I think, therefore I am”. Similarly, we must make assumptions (including the assumption that we do in fact exist) in order to even attempt to make sense of the world.

With perception’s potential deceitfulness, intuition’s unreliability and seemingly unfounded conclusions, and logic’s possible errors, it seems as though there is no way for human beings to truly “know” anything. In the grand scheme of things, human knowledge is indeed incredibly limited. But we cannot go through life without attempting to know and understand anything. Even if our knowledge is imperfect, we must simply try to make it as correct as possible. The best (most accurate) method for doing so seems to be by utilizing logic based on the most accurate assumptions possible, similar to the process used by Descartes to create his philosophy.