Everything we know about the world has passed through our senses. We assume that we can believe what we perceive. But this is not exactly true. In fact, when our senses encode and process information, that information is changed. Furthermore, how we think about the world also affects how we perceive the world. So we can't really believe what we perceive. It may be more accurate to say that we perceive what we believe. Take this class and you may never think about the world the same again.