This chapter explores those mental entities that are formed by people over the course of their life in society. The author examines the personality as a real mental entity—or a set of stable mental structures that include: beliefs, worldview, values, moral principles, sense of duty, and responsibility. These are formed and remain in the person’s mind as part of their personal objective mental reality, but they have referents in physical reality. Beliefs, worldview, values, morality, duty, responsibility, and other mental entities—often referred to collectively as a “structured set of meanings that are significant to the individual”—are basically stable verbal representations of the world. They reflect the individual’s generalized personal experience as well as the internalized collective experience. Over a person’s lifetime, many of these acquire the status of subjective truths for the individual and begin to guide their behavior, ensuring both personal and social stability. Although social in nature, they form the “mental foundation” of personality, defining perception, modes of thinking, interpretation, and action. The mind seeks to preserve its coherent verbal content and actively resists external influences upon it. This is manifested in resistance to alternative views and in the collective defense of society’s objective mental reality.