Russell summarizes his ideas about types of knowledge and how they can be understood as either true or false. He asks a foundational question: “Can we ever know anything at all or do we merely sometimes by good luck believe what is true?” (80). Russell first defines knowledge as a type of true belief that is self-evident. He reminds readers that there are different types of knowledge, each with their own challenges. Knowledge by judgment relies on personal intuitive reasoning and is, therefore, more prone to error than knowledge of acquaintance, which relies on perception across multiple instances.

Knowledge can be determined to be true when it is self-evident, but knowledge is only self-evident to an individual. People have subjective experiences of the world, and they build knowledge based upon their unique sets of sense data. Universals, on the other hand, do not display this same private nature. They are found by many different people, revealing their unique brand of self-evidence. While self-evidence through connection guarantees truth, humans can never be fully certain of this type of knowledge. This is because people habitually conflate judgment and perception.