This text examines the fundamental problem of atomism, focusing on the question of the basic nature of the world. The author explores whether reality is based on the smallest material bodies—the ultimate "building blocks"—or on tiny fragments of happening, referred to as "events." Within the framework of contemporary theoretical physics, this question remains unanswered and unresolved. A primary example of this ambiguity is the quantum of energy, which can be viewed as a particle (a body) in certain contexts, yet manifests as a wave (a non-particle or process) in others. This wave-particle duality suggests that the traditional conception of indivisible physical units is insufficient for describing modern scientific findings. The article reflects on the tension between substantial and processual interpretations of existence, highlighting that the choice between these two approaches significantly shapes our ontological understanding of physical reality.