This text challenges the existence of individual "percepts" as distinct entities, characterizing them instead as psychological constructs designed to explain the phenomenon of perception. The author proposes that perception should be understood through the concept of "reactivity," defined as the fundamental capacity of all real entities to respond to others. This ability is viewed as a developmental process, evolving from the simplest "event-entities" at the level of quanta or atoms to the most sophisticated levels of human perception and cognition. While it is inappropriate to speak of "percepts" regarding subatomic particles or molecules, the author asserts the necessity of acknowledging their inherent ability to react to their environment. Ultimately, the text shifts the focus from a purely psychological interpretation of perception to an ontological view of reactivity as a continuum connecting physical interactions with advanced human thought, suggesting that perception is an evolved manifestation of a universal property shared by all being.