An Essay on Knowledge (Plato, Descartes, and Hume)

Knowledge is Perception

            Perhaps the foundation for unlocking other crucial questions in life begins with understanding what knowledge itself is.  After all, how can one unlock mysteries without even a grasp of what it is to know the mystery or the answer to it?   Plato makes an attempt at building this foundation by stating that knowledge is perception by using a dialogue between Socrates and Theaetetus to illustrates his ideas and reasoning.

            The basis of knowledge is perception is built upon two main factors: “the thing acting, and the thing being acted upon”(Plato 42).  The sum of these two factors is a perception of an object.  For example, there may be a rose in a vase in my kitchen.  In order for me to produce a perception I need to know the object, and the objected it is affecting.  In this instance the object, or thing acting, is the rose and the object it is affecting is my nose (assuming I am perceiving it through the sense of smell).  Together, these two create the way I am to olfactorily perceive the rose.  To lack either of the two crucial parts of perception would prevent me from perceiving it.  If there is no rose, then obviously there can be no impression upon any of my senses.  Also, if there is no sense of smell of the rose, I cannot perceive it (assuming again that all other senses are void). 

            What makes this an interesting theory is how it affects each human.  Since half of the perception comes from the object being acted upon, there is ample room for differences in perception from person to person.  This applies both to sensual experiences, such as smell, and I believe as well as opinions.  Take for example the story Plato gives of Socrates drinking a cup of wine.  When Socrates is healthy the wine tastes sweet and delicious to him.  However, if Socrates becomes ill it may affect how the wine tastes to him and make it taste bitter.  Thus, the wine to healthy Socrates is sweet.  Just as equally, the wine is bitter to sick Socrates.  Both have true perceptions for themselves of the wine, although they are completely opposite.  From here Plato shows that a perception must be what really is, or “homo-mensura”.  In essence this is the connection between perception and knowledge.  This means that what I perceive is the truth for me, and I cannot be incorrect since knowledge is relative to the perceiver.