This text explores the ontological concept of being as an event that unfolds within time and space. Every intra-worldly being is characterized as a happening that 'temporalizes' itself through its existence, possessing distinct beginnings, endings, and spatial boundaries. The author posits that beings are not static entities but active processes of 'becoming.' A central theme is the interaction between beings; any new entity reacts to others, and such reactions inherently carry the character of an action. This capacity for activity is rooted in the subject's own performance of its being, which the author identifies with the Greek term energeia, meaning an internal act or exercise of power. Existence is thus redefined as a dynamic inner performance through which a subject realizes itself. The document presents a philosophical framework where being is inseparable from doing, and where reality is seen as a web of interconnected events and subjective actions, moving away from traditional static interpretations of being toward a more fluid and relational understanding.