This treatise on epistemology is a defense of knowledge of the physical world, which refutes a collection of the history of philosophy's most popular arguments, such as the argument that sensory perception is capable of deception, the argument that sensory experience is subjective and therefore incapable of knowing objective reality, the argument that perception experiences only a series of sensations and therefore can never infer direct knowledge of cause and effect, and the argument that reason assumes its own validity and therefore rests upon a circular argument. Along this illuminating intellectual adventure, this essay discusses language, logic, how the human brain works, what it means for something to be objective or subjective, and how reason and perception function. Required reading for fans of philosophy, or for anyone who has ever had doubts or deep thoughts about how it is possible for us to know what we know and is looking for a well-reasoned, thoughtful, logical defense of knowledge.