The text examines the philosophical problem of subjectivity, tracing its perception from common usage to its historical roots in Ancient Greek thought. It focuses on the distinction between mere opinion (doxa) and true knowledge (episteme), which established the fiction of inner vision or pure intellectual perception independent of physical senses. This tradition relied on numbers and geometric shapes—mental constructs rather than physical realities—to model the world. While such models are effective, the author emphasizes the need to define their limits and revise the classical concept of episteme. A central theme is the distinction between the subjective act of thinking and the objective mental models toward which that act is directed, often discussed in the context of intentionality. Numbers, for instance, exist independently of subjectivity, even though they are accessed through subjective mental operations. The text concludes that rigorous thinking must involve subjective performances that remain uninfluenced by personal subjectivity, thereby preserving the integrity and independence of the thought content.