This text explores the ontological nature of events and their fundamental relationship to the world. The author defines a true event as an internally integrated unity that unfolds from its beginning to its end. A central theme is the integration of an event into the world, which occurs through contact and interaction with surrounding events. Without such connections, an event leaves no trace and effectively fails to participate in the world's context. The world is thus characterized as a system built not on isolated events, but on their capacity for communication, action, and reaction. The text further examines the differences in reactivity across various levels of events. Lower-level events possess more limited means of interaction, which complicates their identification and understanding from the perspective of higher levels. This hierarchical structure and the limited sensitivity of lower levels impose significant constraints on our cognition of reality. The author suggests that these epistemological consequences are profound, as the true properties of lower-level events may remain partially inaccessible to higher-level observation due to the necessity of mediation.