Most people, myself included, like to believe that they possess knowledge about the world around them. I thought that many of the beliefs I had were irrefutable and obvious facts based on common sense. I believed that I had at least some knowledge and that I existed. However, upon reading the writings of David Hume, my beliefs about knowledge and the world have been quashed. Modern philosophers like Hume were most concerned with epistemology--what they could and could not know. They defined knowledge as a true and justified belief, one that is absolutely certain. The all-important question is this: is there any indubitable knowledge in the world? To answer this question, we must first realize that most of our beliefs about the world are based on perception, the use of our five senses to become aware of the world.

When I perceive the world using my five senses...